Had my Sprint iphone 4s (which was working great on Ringplus, a Sprint MVNO, I am no longer a Sprint customer) unlocked by calling Sprint, at first he tried to do domestic unlock then ended up transferring me to the international side, who said they'd give it a shot. A couple days later I get an email saying it's unlocked. I popped in a T-Mobile SIM to test and it worked great, and still does. Should have known then it was a little too easy!
But now when I put back in the original Sprint SIM (which connected me to Ringplus) it says No Service. It's like it forgot how to connect to CDMA, in Settings / Carrier only AT&T and TMobile are listed and Auto won't connect to Sprint/Ringplus. I think I tried everything; first resetting network settings, then wiping everything and starting fresh, to backing up and restoring in iTunes (which said congratulations your iphone is now unlocked), even upgraded to latest 8.2 and tried starting fresh and also via restore, both not working. Phone has never been jailbroken or unlocked/hacked in any way.
Anyone know how to fix this? I wonder if Sprint customers still on Sprint are now not able to connect to Sprint as well? @acadiel were you able to fix this issue, or is this a one-way ticket to GSM only as you previously posted?