The possible reason for this deletion is because people don't always commit to the terms and conditions of xat listed (here), Some say it could be for being inactive for long periods, which I doubt this would be the reason in your case, accounts don't get deleted for being inactive on xat especially you said that you paid money on your accounts! However you can simply just create a ticket or get a volunteer to create one for you to know what was the reason!
On one hand you will get a response for your problem, you will get your account back hopefully as long as you haven't done anything that violates terms and conditions of xat but on the other hand you will have to wait for that response a good amount of time, don't be impatient tickets that fall under the following departments (Account hold, block, report scam or phishing site) which can be found on (here) are having a high volume of tickets, they are sent roughly on daily basis, they are answered in the same order they were received in. Again hopefully you get your account back and good luck!
If you have any other questions or inquiries post them here if about another topic then create a new thread!