No Mobile data.

Bought the phone yesterday and cannot get mobile data but phone coverage is fine. After hours of troubleshooting from google and forums and factory resets I rang Talk mobile/ Vodaphone. Helpline talked me through what i'd already done apart from adding a new APN, although i could not do this as the only option in the advance setting is to 'reset to default'. Cannot amend anything else as it is all greyed out. It does recognise the sim as a vodaphone account however in the APN. I shall be returning the phone rather than having to pay to visit a technician as suggested by vodaphone.