Hi @vlady50 I suggest you try turning your phone off, waiting a minute and then turn it back on (to force it to reconnect to the mobile network) to see if that fixes it.
If that doesn't work, you should see if there are any network problems where you are using the service status checker: https://community.giffgaff.com/t5/Service-Updates/Service-Checker/td-p/17646124
If there are no network problems by you, see if doing a manual roam helps as described here http://community.giffgaff.com/t5/Using-giffgaff/Force-the-change-of-SMS-settings/ta-p/4871794
Finally please try swapping SIMs with another phone to see if there's a problem with your phone or the giffgaff SIM.
@vlady50 did you activate SIM with minimum ten pounds top up or buy a 6pound minimum goody bag via card payments to activate the SIM also have your tried restarting device to kick start it
If yes is phone unlocked or on the 02 network if not it won't accept the giffgaff SIM card
If is unlocked and a I phone please try switching of and on your I messages wait until fully loads when completes do same with face time settings when all completes restart phone to sync SIM and number with your I tunes account again
If not and I phone and its unlocked and restarting phone don't work please
inquire with agents click nearest topic to activations use box provided and explain given the activation code of SIM card or long SIM serial number from back of SIM your full name and address last time topped up by what method and how much
contact the agents
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