I just read about a similar experience.
In short, I paid and the transaction was confirmed. In their account area the invoice appeared as unpaid, so I emailed them asking about that.
They replied asking how I was trying to pay, that the payment method I used is no longer accepted and that I should send screenshots of the paid invoice.
I was going to send a screenshot of my payment, but when I tried to log in, my account no longer exists.
I feel duped.
They are doing this all the time and keep on denying. It's our own fault... Their attitude is really bad. My advice: stay away from area 51.