Mobile Phone Glitch

Don't know if any of the forum members are mobile phone experts.For some odd reason when I went to the UK in August my Spanish Digimobil sim wouldn't get data.They sent a new APN but it never fully worked so I used friends and families wifi.When I got home again no data again although calls and text fine.They weren't very helpful so I started using the Tesco sim which gets 4G in both sim slots,but after 3 months I fell foul of their well hidden T&Cs which block roaming data after 12 weeks out of the UK.Yesterday I bought a Lebara Spanish sim and it's the same tale,calls and text but no data connection.I've tried switching slots,leaving the Tesco sim out of the phone to try to rule out any hardware problems,but still the same,this morning borrowed a friends Giffgaff sim which connects straight away to a 4G signal.It's as if something in the software is blocking data from all non UK sim cards.

Probably depends on the phone you are using.

You may need to update carrier settings (if iphone) or similar to kick it into action.
Was data roaming switched on?

It sounds like the issue could just as likely be your carrier though.