How to force a specific network operator?

[bellocarico]

I'm currently abroad and my carrier (three.co.uk) only provides data connectivity via a single foreign carrier (Proximum in Belgium to mention one). However by default android always connect to the strongest signal carrier (e.g. Base) and this leaves me disconnected. I need to periodically go into the settings, disable automatic network operator selection and select Proximum manually.

Is there any way to specify Proximum as the preferred network operator or even blacklist the other operators so that they can't be automatically picked up?

P.S. I'm also surprised to find out that going back into the settings I find the network operator again set to "auto" after I select Proximum as the preferred carrier.

Any help?

Thanks

 

[Hadron]

I'm surprised both that the phone switches back to auto and that it connects to a network which your carrier does not work with even when your partner network is available (connecting when your partner network is not available makes sense, as that allows emergency calls).

There used to be a way of selecting a preferred network, but it is something I've not done for many years, and hence many Android versions, so I don't know currently. I also think that the option was only visible when you had a list of roaming networks available, which means I can't check now since I'm not roaming. All I can suggest is the standard Android technique of press and hold on one name and see whether it gives you any options (or look for a little 3 dot menu anywhere on the network selection screen).

 

[bellocarico]

That's the first thing I tried. Press and hold on the network operator produces nothing. All I can do is to select the operator one off until it automatically decides to roam onto a different operator or wait for me to re-enter the menu where the option to automatically select operator is always set.
There are no 3 dots, nor other options are given on that menu.

OUI 4.1
Android 12

 

[Hadron]

So a Samsung. Yes, that's what it looks like in my home region, sounds like it's the same when roaming.

Unfortunately what I don't know is whether other options were removed in Android updates, removed by Samsung, or are hidden somewhere really obscure. But I can see no sign of such things on my phone (also Samsung's version of Android 12), whereas they definitely used to exist in other brands with Android 2-5 (can't recall for 8-11, barely used 6 or 7).