iPhone 5 has suddenly stopped connecting to the internet away from home

My iPhone 5 has suddenly stopped connecting to the internet when away from home. It was fine last Wednesday, then on Thursday all I got was 'Safari is no longer connected to the internet'. I cannot use the Messaging, Find my Friends etc.

As far as I know I have not done anything to alter any settings, but I did change my password on Wednesday - which works, so I think that's OK.

Has anyone any idea what is happening?

ictoau