Why did you mark your own post as a solution?
Does this mean that the issue has been resolved since you posted?
If not then ...
What happens when you try to buy a membership plan here?
Any error messages?
When were you last able to successfully buy a membership plan?
Is your registered payment card still valid, not frozen via your online banking, and there are sufficient funds in the account if it's a debit card?
If you need to contact 48 support about this then see the links in my signature below.
