I can't view my account and data balances,as well as can't make or receive calls

I moved to UK recently and since then I have not been able to make calls to Nigeria. I do receive calls though. What could be the problem.

I just subscribed for the MTN CUG about 2days ago. Ever since, I have not been able to make and receive calls. I even tried calling MTN customer care line to relate my complain...

This started on the 14 of Feb. And I still can't receive calls

I can’t make calls with my line from the uk but I can recieve call and I don’t know why .. I need this thing resolved