Waiting a year for payment

I saw a Bestmed patient some months ago. My account was never settled by bestmed. Every time I phone in, I am told to send my bank details. However, I have already sent my bank details on numerous occasions and I am now tired of phoning Bestmed. I just want to get paid please. In any case, I have had Bestmed patients in the past and I used to get paid - into the same bank account. What is going on?