Can you firstly click onto this link https://giffgaff.com/dashboard
and make sure that you do actually have,either an active goodybag or enough credit,cheers.
If you could also please try turning your device OFF,wait 5 minutes,then turn your device ON again,as this can help in most cases.If your issue has not been resolved,check the signal in your area,by visiting or clicking onto the link below. Please be aware that the website is updated hourly, so there may be a current issue that is not showing at the moment. Keep checking the signal checker website over the next few hours or so,cheers 😀 . http://bit.ly/ggservice If the signal checker is showing NO issues,you could also perform,a manual roam,which basically is searching for networks on your device.Go to your phones "settings" and Select mobile network options and Change the Network Selection Mode from Automatic to Manual and list of available networks will be displayed after a few moments.Select any other network that is not your home provider network and After a few moments you will see "No Service" on the display.Now select your home provider(which is o2) network and change the selection back to Automatic 😀 .
You may also have to set up your device manually,and as you have not posted your make and model of device,here are a few links for the most popular devices,cheers 😉 . Android devices - http://goo.gl/iEsCXZ
All other devices-http://goo.gl/t3UbYT
Also click onto the link below 😉 . http://community.giffgaff.com/t5/Tips-Advice/The-giffgaff-Internet-Settings-Guide-Setup/m-p/2066679
Please remember that MMS are NOT included in any goodybag allowances,and to send MMS,you will need to have credit on your account,MMS are 16p each to send. If you have any further issues,please take the time to click onto the links below to take a look at two more fantastic guides,thanks again 😉 . http://community.giffgaff.com/t5/Using-giffgaff/Internet-does-not-work/ta-p/7435922 http://community.giffgaff.com/t5/Tips-Advice/The-giffgaff-Internet-Settings-Guide-Setup/m-p/2066679