I have an iphone 4s. I have a good signal and 3G but making and receiving calls is intermitent. I don't realise the phone is not working until I try and make a call and it fails. Or I try calling my own phone and it doesn't work.
What carrier are you on? Are you on prepaid in Europe?
Does the call complete to the carrier's hotline?
Does data work?
Do calls work on a different tower?
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