Product: Credit card or prepaid card

My Synchrony XXXX XXXX account was changed to XXXX XXXX XXXX XXXX XXXX XXXX XXXX in XX/XX/XXXX. On XX/XX/XXXX I mistakenly made a payment of {$2600.00} to the old Synchrony account. When the XXXX statement came showing a missed payment of {$2600.00} I discovered the error and called the number on the back of my Synchrony XXXX XXXX XXXX and was connected to XXXX. They said they would correct the error and no interest would be charged, I just need to fax my bank ( XXXX XXXX XXXX XXXX ) information showing the transaction. 
This I did on XX/XX/XXXX. When the XXXX statement arrived and no correction had been made, I called again and was told it could take up to two billing cycles to clear. XXXX came and still no correctio and I called. They then told me my fax needed to have a statement from the bank showing the transaction with a tracing number. I immedatly went to the bank and they mailed me the requested information ( attached ) and I faxed XXXX this information on XX/XX/XXXX. XXXX came and still no correction. I called them and they said they only received the cover sheet from my fax. I was frustrated and asked the XXXX representative ( XXXX ) for a good number to call Synchrony Bank myself and he gave me XXXX. This was XX/XX/XXXX, XXXX. The representative was helpful, sent me a replacement copy of the Synchrony XXXX XXXX statement showing the {$2600.00} credit balance ( attached ) and that he would submit a request for refund and it would take up to 17 business days to receive a check. I received an e-mail from Synchrony asking for me to take a survey on how the dispute was resolved. I did not open it as the 17 days had not expired so in my mind it had not been resolved yet. When I did not get any response after 17 days, I opened the email and it said it had timed out and I could not submit a response. 
I called back to Synchrony on XX/XX/XXXX and was told they would resubmit the request and it would take XXXX weeks.. I grew leery and called back after about a week and was then told that my account was closed and they could give me no more information. I was passed off to XXXX. I was told by XXXX to refax the information they said they only received the corer page on. This I did on XX/XX/XXXX. They said they did not receive it at all, so I resent it again on XX/XX/XXXX, XXXXThe representative I spoke to on the XXXX had told be to call back in the evening and insist they tell me if they received it. This I did and it appeared to annoy them but was finally told they had it but " unfortunately, Synchrony had my money and I would have to deal with them ''. I immediately called Synchrony and this time the automated answering service no longer recognized my Synchrony account number and I had to go through a torturous process to get a live representative, but even at this time he could see the {$2600.00} balance and gave me a fax number to sent my bank transaction Info. Fax number XXXX XXXX. On XX/XX/XXXX XXXX  The XXXX XXXX tried twice to send it and both times it failed. I called back the same day And the Synchrony Rep ( XXXX ) gave me the same fax number but I asked to speak to a Supervisor. This supervisor said I needed to take it up with my Bank and she offered to do a conference call. I agreed and she called XXXX XXXX XXXX XXXX, but by the time I got through their automated answering service, The lady from Synchrony was no longer on the line. I called XXXX again a exhausting process - and again the reps name was XXXX XXXX He again saw the {$2600.00} and I asked to speak to a supervisor. This time I was met with hostility and was told XXXX had purchased those accounts and all balances were automatically transferred to them and Synchrony no longer had access. I told her " XXXX had just looked it up and told me he saw the {$2600.00}. She said she did not know who XXXX was and repeated the same spiel. I tried to get her to tell me the date and amount of the " XXXX '' transfer took place and she angrily said she had told me XXXX times that Synchrony no longer had access to the account. after about XXXX minutes we ended the call. 
I have sent certified letters to both Synchrony and XXXX to aske that they resolve this issue. Yesterday I drove down to XXXX to what was suppose to be a Synchrony Bank but when I arrived I was told they had moved out and now had only call centers. 
It is my sincere hope that this complaint will help end this XXXX XXXX XXXX