Is there anything more I should try before replacing my SIM card? I have reset all network settings. It looks like my Wi-Fi is connected, but the phone still tells me "No connection" and I can't send/receive texts or phone calls.
Have tried all those helpful ideas, and the service is running fine on my laptop. I'm going to give the battery-changer another chance to take the new battery out, check that everything else is properly connected/etc?, and see what the future holds. ...
It's not blacklisted and thank you for pointing me in that direction. I had not thought of that possibility. We tried the SIM card in another phone... no problems encountered. Thank you for the ideas, though. I appreciate them!
Oh, yes. This is a new problem but not a new phone or SIM card. It happened after they changed the battery due to need to abnormally frequently need to recharge it. But a good check, nonetheless. Thanks!