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iPhone: Troubleshooting issues making or receiving calls
iOS: Troubleshooting Messages
Have a nice day,
Apparently the issue was solved (and I hope definitely) by the carrier TIM. They gave me a vake call talking about very vake problems on the network, and then all was working fine receiving calls and text messages.
The carrier on the phone shows to have an update available, but I'm a little concerned to update since my phone is working well at the moment.
Not sure whether you're Italian and if you heard of similar issues, if you did I would like to hear.