@traceybryant46 please check your local area for any networking issues via here services
https://giffgaff.com/coverage-and-service#network can you please pop your full postcode in here to check for any network issues if shows none please try a manual roam as explained here http://is.gd/manualroam
or switch on and off your airplane flight mode a few times to refresh your network again
Or try a soft reset by holding down the power button and up and down volume button at same time until phone reboots its self and see if works then Also if it's and unlocked I phone try a reset of network settings as shown in this picture
Are you able to send texts to these numbers: 43430 and 2020 at all?
It could be to do with your APN.
Please check your APN settings and ensure you have “giffgaff.com” set.
@traceybryant46 if the information I've given don't work please inquire with the agents about it via here and click on calls texts and data issues then use the how can we help box and explain the issue contact the agents
remember allow from a few hours up to a maximum time of 24hrs for agents replies which will show here when logged into your account
Remember agents work from 8am until 11pm daily