I've tried to turn on voicemail in my new iPhone 6, but I get an error:
"Voicemail Unavailable. Unable to connect. Try again later."
This has happened over several days. I reset my Network Settings but that didn't help.
Fixed with Tmobile Chat Help. I set mine up by dialing 123 and doing it on the phone. My wife fixed hers by restarting the phone.
Have you tried to use Google Voice - it works really well and is free
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