Product: Credit card or prepaid card

A credit card with Arhaus furniture store ( Comenity Bank ) was opened XXXX XXXX, 2019. The initial purchase was made using a promotion that was no interest for 1 year. Subsequent purchases were made under a 6-month promotion period of no interest. Each and every month, the minimum payment was made on time. The six month promotion balance was paid in full on time. The 1 year balance was coming due. I was concerned that I would not be able to pay the balance remaining of {$10000.00} by the XXXX due date. So, towards the end of XXXX. I reached out to customer service at Comenity Bank to see about an extension. I was transferred to the financial hardship department. My plan was to pay a portion of the balance and the remaining balance would fall under a payment plan with with the financial hardship department. However, in order to do that, they needed a final balance to work with. I was told to make my payment and then call back. Given that my husband 's salary was cut due to the pandemic and our daughter has many expenses due to special needs, I opted to open a new credit card and use a balance transfer to pay down the Arhaus balance. This account with XXXX ( XXXX ) was approved and an e-payment of {$3300.00} was authorized on XXXX XXXX. Unfortunately, the payment was rejected by Comenity Bank on XXXX XXXX. I was not informed of this until I received a letter from XXXX via USPS on XXXX XXXX. The reason from Comenity Bank was " invalid account number ''. This was NOT correct. I called the bank and they confirmed that the account number was correct. The representative could not understand why the payment did not go through. I also called XXXX and they said the same thing. Comenity said to try again. I did. The same rejection happened. I called Comenity again and spoke with many representatives ( escalating the issue to supervisors ). Again and again I was told that everything was correct : account number and bank name. Hours were spent on the telephone with Comenity representatives ( all calls were logged by them ). At this point, I am past my due date. Frantic, I applied for another credit card on XXXX XXXX, now with XXXX  XXXX XXXX with a balance transfer request for {$6000.00}. Also on XXXX XXXX, I called XXXX again and with the representative on the telephone we did the transfer together ( prior attempts were done online ), but this time, I said try Arhaus ( not Comenity Bank ) since all other attempts failed. This transfer, for {$4000.00}, was ultimately successful. 
The XXXX  XXXX XXXX account was approved and the payment of {$6000.00} to Comenity Bank was made on XXXX XXXX. The final amount of {$76.00} was e-paid from my checking account. I am not charged {$3400.00} in interest charges on the open balance. I have tried many times with many representatives from Comenity to get the interest credited, but no one can help me. I was told to file a dispute online on their website. I did so with all documentation showing the attempted payments uploaded. Letters were sent back to me indicating no back-up documents were sent. They documents were mailed on XXXX XXXX and still no response. Each supervisor that I escalated to told me that they could not get in touch with anyone in the dispute department, " they don't have a way to get in touch ''. I was left on my own. I mailed the documents again this time certified mail and have proof that they were delivered. Yet again, a letter saying no documents were provided so the interest charges stand. I have spent hours on the phone - and still - all reps tell me sending to Comenity Bank was correct. They never heard of sending to Arhaus. Even their statements say Comenity bank as the payee. Yet, the payment did not go through and now they are enforcing a huge interest charge and won't even speak with me. I went to the store and the manager said she would reach out to her rep, and the manager never got back to me ( I emailed her to follow-up too and no response ). Finally on XXXX XXXX I got someone named XXXX XXXX on the phone. She said she would be my contact now and needed to get the paperwork from the dispute department. This would take a couple of days. She called me back 2 days later to let me know she still had not received the paperwork. This was greatly appreciated. However, it is now XX/XX/XXXX and I have not heard from her. I left messages for her on XX/XX/XXXX, XX/XX/XXXX and XX/XX/XXXX with no return call. Comenity Bank 's customer service is shameful!! And during a pandemic no less. HOURS of time have been spent. I have not paid the interest charge nor do I intend to. I am not trying to get away with anything. Payment attempts were made but not successful due to Comenity 's error and lack of knowledge. The balance was paid in full within 3 weeks. I am an honorable person with a good credit history. Please help to resolve this. Thank you!