Galaxy Note 10 - can't get VOLTE to work

[rbjhb]

I have a Galaxy Note 10. I have just joined US Mobile on one of their Warp 5G plans. Before signing up, I entered the phone's IMEI to confirm that my phone is compatible.

I have manged to get my data service to work, but I have no mobile network service, in other words, I cannot make or receive calls or texts. I have followed all of the instructions given by US Mobile - I have set my Network Mode to LTE Only, I have turned off Data Roaming, and I have turned on VoLTE calls. I have put in the APNs that they listed. All that they can suggest is to reset my network settings, but I'm loathe to do that because I don't want to lose my saved Bluetooth and Wifi connections. And I suspect that might not work anyway.
PS I can't find Wifi Calling on my phone - could this be related or give a clue as to what the issue could be?

Any help would be most appreciated.

 

[Hadron]

When you say you got your "data service" working but have "no mobile network service" that sounds contradictory, since "data service" implies a mobile network (as opposed to WiFi). So just to be completely clear, you have a cellular connection, you can see signal bars and download with WiFi turned off, but you cannot make calls? Or is it something else, e.g. you have WiFi data but no cellular connection?

WiFi calling would be relevant in the second case, but it's not a solution because you could only make calls when connected to WiFi. On my Samsung (a bit newer than yours, running Android 13) WiFi calling is in the settings of the Phone app rather than in the system settings - I don't know whether you've looked there.

If it's the first case, possible explanations I can think of are:

1) something odd in the setup of your phone (which is what they are hoping when they suggest a reset)
2) something wrong with their SIM
3) something wrong with their configuration of your account

If you are reluctant to reset anything then the ideal would be if you had access to another compatible phone that you could test the SIM in. If calling worked in a different handset that would tell you that the problem was in your phone somewhere, whereas if it didn't that might point the suspicion at their SIM or their setup of your account. But if you don't have that option then it's hard to work out the cause except by trying things and seeing whether they make a difference.

 

[rbjhb]

Hi Hadron, thanks for your reply. I have 4G LTE service, but no signal bars. I have that symbol that looks like a no entry sign (see attached screenshot). When I try to make a call, I get the message "Mobile network not available". I cannot receive or make calls or texts.

Unfortunately I don't have another compatible phone to use to test the sim - I am travelling, and my 'backup" phone is an older phone that is not compatible with this "Warp 5G". I doubt there's any issue with the sim because my data service is working perfectly. I'm pretty sure it's something to do with my phone. Maybe I must just bite the bullet and do the damn reset. I had to borrow someone's phone at the airport to call the rental car company when my flight was delayed!

 

[Dannydet]

I'm thinking they gave you a faulty Sim card. It's happened to me before.
I'd contact US mobile and get a new Sim.

 

[olbriar]

It happened to me once as well. It happens.

 

[Hadron]

Yeah, you don't have any mobile connection at all there. I don't see any warning about it being an unauthorised SIM, so my guess would be either a SIM fault or the carrier have fouled up and failed to enable service for that SIM. Like the others, I would think that a faulty SIM is more likely (I've never been given one that's DOA, but I've had a couple go bad in use, so it's far from unknown).

Just on the off chance, have you done a scan for available networks? Just to check that you aren't in a blackspot for the new carrier (if a scan shows other networks but not yours that might be a possibility).

 

[rbjhb]

It doesn't let me do a scan - the Network Operators option is greyed out.
Also, I've been in lots of different places across different states (Texas, North Carolina, Massachusetts, Maine) - I couldn't possibly have been in blackspots all over, including on the road in between places!

 

[Dannydet]

Uh, yeah we already told you it's a bad Sim card

 

[svim]

...... All that they can suggest is to reset my network settings, but I'm loathe to do that because I don't want to lose my saved Bluetooth and Wifi connections. And I suspect that might not work anyway.
.....

That does appear to be a big stumbling block as far as actually fixing the problem. Yeah, it might not be a solution but there is a chance it will.. Weigh your reluctance to move forward against being able to use your phone as a cellular service phone again. Losing saved Bluetooth pairings just requires you to re-pair your Bluetooth devices, losing saved WiFi network passwords is more annoying.

Before doing a Network Reset try installing something like this retaining WiFi password app to backup your saved WiFi network info:

WiFi Password Show Connect - Apps on Google Play

Show All WiFi Password, WiFi Speed, Wi-Fi Connect & Wifi Connection Manager

play.google.com

 

[Hadron]

"Network operators is greyed-out" - I've never seen that even with a carrier-locked handset, but of course I'm not American and your carriers do seem to be the most controlling in the world, so maybe I shouldn't be surprised

I still don't understand you saying that your data service is working though: the screenshot you posted showed no mobile signal, which means no cellular data as well. So how can you have data when you have no cellular connection (other than WiFi, which is separate from the cellular network)?

 

[rbjhb]

The handset is not carrier-locked - I bought it on amazon and have subsequently used it with local sim cards at home in South Africa, in Turkey, in Qatar, in Pakistan, in India, in the UK and in Spain. (By the way, it's been illegal for many years in South Arica to carrier-lock a phone)

From my screenshot, you can see that it shows 4G LTE. I assume that's how I'm getting data service. I have used the internet on the phone with Wifi turned off, and in public areas with no Wifi. As to how it can be possible to have 4G LTE data service yet not be able to make or receive calls or texts - well, that's what I'm here to find out!! It's got something to do with the fact the this US Mobile sim card is using what they call "Warp 5G" and makes calls using VoLTE rather than using "normal" cellular networks. At least that's what I've read. If someone can explain how tht all works, I'm all ears!

 

[Dannydet]

I think you've discombobulated your device network settings altogether and that may be the reason for your issues.
Do a factory reset please and see if your US mobile service will work.
We can't help nor suggest anything more without you trying this.

 

[rbjhb]

@Dannydet:
First you say, "Uh, yeah we already told you it's a bad Sim card" and now it's, "I think you've discombobulated your device network settings altogether and that may be the reason for your issues."
I appreciate that you're trying to help, but you seemed so certain earlier it was a bad sim card and now you tell me you can't suggest anything more without me doing a factory reset.
Let's see if the new sim card arrives tomorrow.

 

[Dannydet]

Well let's see....
After re-reading your original post, it leads me to believe it MAY be your network settings. We've never dealt with an issue such as yours, so it's going to be one or the other.
Hey if you have a better idea, go for it.

 

[Hadron]

From my screenshot, you can see that it shows 4G LTE. I assume that's how I'm getting data service.

But it also has no signal bars and an explicit "no signal" symbol (that crossed-out circle). That's what's confusing: those signal bars aren't for a voice service, they are the cellular connection strength, and it seems to be zero. Is it always like that, or was that screenshot just taken at a time when the signal was zero?

I have used the internet on the phone with Wifi turned off, and in public areas with no Wifi. As to how it can be possible to have 4G LTE data service yet not be able to make or receive calls or texts - well, that's what I'm here to find out!! It's got something to do with the fact the this US Mobile sim card is using what they call "Warp 5G" and makes calls using VoLTE rather than using "normal" cellular networks. At least that's what I've read. If someone can explain how tht all works, I'm all ears!

LTE = 4G data connection. It doesn't have a dedicated voice functionality, so originally 4G phones had to switch to 2G or 3G to make voice calls (they did this automatically, so you wouldn't notice unless you were watching the status bar). VoLTE = Voice over LTE, which is like Voice over IP (Voice over Internet Protocol, i.e. internet calling), a way of using a data connection to make a voice call. "WiFi calling" is another example of this idea. That's the way telecoms is going: all networks are just data networks.

So the addition of VoLTE allows 4G phones to make voice calls without switching to one of the older protocols, which in turn is what makes it possible for the networks to turn those off and re-use the spectrum for newer, higher-capacity systems (4G and 5G). So if for any reason you don't have VoLTE available, and can't use the older protocols, you could still have a data connection with no voice capability. You have turned on VoLTE calling, but it seems not to be working. The question is whether that's because your phone's implementation isn't compatible with your current network's (the worst case), because there's a configuration problem (in either your phone or for your account in their systems), or because there's a hardware fault (e.g. the bad SIM hypothsis), that's the tricky bit to work out: because if all anyone knows is that it's not working that doesn't rule anything out. All I can think of is to try the ones that can be tested (clearing your network settings, asking them to check your account is correctly configured, try asking for a new SIM) in whatever order is least inconvenient and hope one of them fixes it.

(I'm going to assume that greying-out of the "network operators" on an unlocked handset is a consequence of using that network's SIM, because I've no other explanation for it. So I'm afraid I'm still going to call your carrier a control freak ).