Product: Checking or savings account

On XX/XX/year> my car payment for XXXX XXXX  was submitted to my account at Current XXXX XXXX XXXX XXXX ) and the payment shows it cleared on XX/XX/year>. XXXX financial initially had my account credited for the payment, but then a week afterwards it was added back to the balance on my car loan. XXXX financial insisted my payment failed, and was returned unpaid. One of the support ticket responses from XXXX said it was returned due to a check truncation entry return, but I have no idea what that means. Ive been jumping through hoops for over two months trying to get it fixed. Ive contacted my bank by chat and email multiple times ( no phone number available ) I disputed the charge, they said they investigated the matter, but wouldnt credit me back the money because they found no error on their part. I emailed the dispute team back and asked for the documents used in the investigation. The email about the dispute said it was my right to request any documentation, and a written explanation of it. I also requested the dispute be escalated, as XXXX still wasnt crediting me for the payment. I didnt receive anything for a while, and asked a few times about the issue. I did finally receive an ACH report from the dispute team that they got from the federal reserve ACH system. No explanation or any other information was included. I asked about escalating the dispute, and got no answer about it. I sent the ACH report to XXXX XXXX and after faxing, and submitting to them with a support ticket I finally had to get the guys at the dealership involved again, because I couldnt get any cooperation. They said they were sending my documents to their resolution team, and it would take five days. Almost two weeks later, on XX/XX/year> I finally got a phone call from XXXX, and I was told that my payment had initially been paid to XXXX, but that my bank reversed the charge on XX/XX/year>, and the money was sent back to my bank account on XX/XX/year>. I never received any money back. They could see this already as my bank statement I sent them shows no returned money, but XXXX still said that is what happened. Ive emailed Current support, and the dispute team since then and received no response from either. XXXX claims they also have an XXXX report that is from XX/XX/year> showing the {$500.00} payment being returned to the bank. I asked for the report on XX/XX/year> and was told I would receive it in XXXX days. I still havent received it from XXXX, and its been 4 days. At this point I have no idea what to do. My money is missing somewhere between XXXX XXXX, and Current ( XXXX XXXX XXXX ), and both companies are blaming the each other. I obviously dont have access to any of these systems, I only know that {$500.00} was taken, nobody can tell me where it is, and Im currently behind on my car loan, getting late fees, and tanking my credit score. XXXX wont stop reporting it as late or stop charging me fees because they claim they arent responsible, and that my money was returned. An ACH reversal doesnt seem like something that happens without the customer requesting it for some serious reason like fraud, and I asked XXXX why it was returned, but they said they dont know why, and I have to ask my bank. My bank wont respond to me, and they claim the transaction was successful, so I cant get any further answers about what happened and why. I really need help with this matter, as Ive done everything I can do besides move forward with my attorney. I would rather not have to do that, but Im not receiving much cooperation from either company. Thank you for your time.