Can't make or receive calls

[RobertV_1974430]

It's been a few days now that I can't make any calls and the incoming call don't reach me, I always get the missed call message after, even if I have full signal, Internet is OK but no calls 

[SmartyTrousers]

I suspect Three have now turned off 3G in your area, and your phone either doesn't support VoLTE (calling over 4G), or has the setting for it turned off, or supports VoLTE but is not compatible with Smarty's VoLTE specifically.

[RobertV_1974430]

ive already done that , i have a sony 1 , it supports everething and it is not loked in any network , also tryed difrent devices and still the same 

[SmartyTrousers]

Already done what?

If you mean a Sony Xperia 1, that handset is on Smarty's list of devices which are not compatible with VoLTE on Smarty: https://help.smarty.co.uk/en/articles/8985136-checking-if-your-device-is-4g-volte-compatible

[RobertV_1974430]

i see , ill swith then .... to bad i had 2 sims with smarty