barry383 it's likely to do with the huge demand on data at moment due to the corona virus
it's likely due to this issue province wide
https://community.giffgaff.com/d/33090533-voice-call-issues-17-march-2020
services
can you please check your full postcode here for any network issues
https://giffgaff.com/coverage-and-service
Remember it's updated hourly so may not of shown last time your checked it
if shows none please
try a manual roam as explained here
https://giffgaff.com/help/articles/how-to-perform-a-manual-roam
or try a soft reset by holding down the power button and volume up and down button at same time until phone reboots it's self
or try switching to 3g only via network settings often improves signal again leave ten minutes and switch back to 4g
also try switching airplane flight mode on and off a few times to update network again
If makes no difference try taking sim out gently clean replace and restart phone again to kick start it and see
