Please restart the device & where possible remove the battery for a couple of minutes and then replace before restarting.
On iPhone devices, go into the Settings and switch on Airplane Mode for a few seconds and then switch Airplane Mode off again. If this doesn’t work then go into Settings, General, scroll down to Reset and select Reset Network Settings only.
On Android devices, pull the shutter down from the top of the screen and switch on the Airplane Mode for few seconds and then switch off again. If this doesn’t work then go into Settings and then More.. in the Wireless and Networks section and select Mobile Networks. Select your mobile provider in the ‘Available Networks’ section and then exit back. Go into the the Access Point Names and make sure you are connected to the right APN for your contract.
If neither of these works then try the SIM card in another handset where possible – if you then have signal it is most likely to be the handset that is at fault. Please contact us to discuss the warranty options, you can either email straight into the Customer Services ticketing system on firstname.lastname@example.org or call Freephone 0800 4704707 Option 1, Option 1 then option 3 and Customer Services will be more than happy to help.