Help Not Found on Network message -- Galaxy S2

[flapjacks1984]

I received an S2 as a gift in October, used it without issue until early January. I'm on a PAYG plan with RedPocket on AT&T's network. I've tried in vain working with their CS team for 3 weeks but have gotten nowhere (sidebar: Red Pocket customer service is horrible, never ever use it or this company ).

I am unable to send/receive phone calls or texts, though I can access voicemail by calling from my landline.

When I try and dial out or send a message from my S2, I get the messages "Not Found on Network" or "Mobile Network Not Available".

I've heard this is an issue with S2, but what can I do to resolve it? This phone was unlocked--would a factory reset have locked it?

Red Pocket said they confirmed with AT&T that I am not blacklisted and should be able to use their network. I tried removing/reinserting the SIM; checking my IMEI status online (says it shouldn't be blacklisted); using a new SIM card (didnt work in my phone, worked fine in another); did a factory reset and had the same results. Red Pocket said they could not provide me the phone settings, AT&T told me I need to get them from Red Pocket.

What other steps can I try to get my phone to work, short of trading this in, sucking up the extra $ for a slightly less expensive PAYG plan and possibly using T-Mobile?

Thank you for any suggestions or help you can give! If I need to clarify or give more information, please let me know--I'm desperate for help!

 

[Rukbat]

When I try and dial out or send a message from my S2, I get the messages "Not Found on Network" or "Mobile Network Not Available".

I've heard this is an issue with S2

I never heard that.

This phone was unlocked--would a factory reset have locked it?

If it had, you'd get a request for the unlock code.

Red Pocket said they could not provide me the phone settings, AT&T told me I need to get them from Red Pocket.

The only settings that matter are the APN settings, and they have nothing to do with making calls.

What other steps can I try to get my phone to work, short of trading this in, sucking up the extra $ for a slightly less expensive PAYG plan and possibly using T-Mobile?

Call 911. If they answer, tell them you're just making sure that your new phone will work in an emergency. If it won't even do that it's a warranty issue - ALL phones, locked or unlocked, good IMEI or bad IMEI, blacklisted or not, MUST be allowed to make emergency calls. (Depending on where you live, it may be illegal to sell you phone that won't.)