Assuming you can get the *228 to connect, I think this might be the solution. I worked on cell phone refurbish final reprogramming that included updating the PRL to one that was very generic - every phone came in with a specific version of the PRL based on where it was from, while every phone we sent out had to be the exact same PRL version that none of them ever came in with (unless they were never used).
It’s quite possible that her phone has been forced into roaming mode due to remoteness, and the ways it knows to connect to operators according to the PRL it has inside it don’t work where she is now. The cell phone will still be able to receive incoming calls so long as the entire network knows where the phone is, but the phone isn’t programmed correctly to know what to do when it wants to call out and isn’t on its home network.
If the *228 doesn’t work, she’ll have to take it into a service shop that can update the PRL for her (assuming that’s the problem). (Which is exactly what I quoted, oh well, I’ll repeat it for emphasis…)