payday nation disappearing payment

I have a loan with payday nation. My last payment to this company was on 9/13/13 that resulted on an overpayment of $210 on the principal only of the loan. (initial loan $600). As advised this is an illegal lender (out of the united kingdom) I revoked ach and requested refund of $210. I logged into my account this morning and see that my account was marked as denied for the payment due today but also the payment on 9/13/13 was marked as denied in the payment history. This was taken from account, it has cleared 2 weeks ago as paid, and it was the payment that that resulted in an overpayment of the principal only. Any advice??? I would say that this is fraud on the part of payday nation, to take a payment that was previously paid and just wipe it away and mark it as denied.