Product: Credit card or prepaid card

I have now made two attempts to send payment to Synchrony bank and they have both been rejected. They denied the accepted payment coupon/financial instrument for {$4900.00} and {$4900.00}. My most recent attempt for {$4900.00} was sent on XX/XX/2023. I also included instructions for the CFO to apply the principals balance to the principals account each cycle for set off. In addition, I provided my notarized Power of Attorney, granting me the capacity to act as the agent on behalf of the principals account. They denied my financial instrument and told me I received a letter written by XXXX XXXX on XX/XX/2023 accusing me of attempt [ ing ] to avoid [ my ] debt, which is not the case. I informed her of the following in my written correspondence XX/XX/2023, which I have attached, In your correspondence, you stated your account balance is {$4900.00}. The phrase account balance is explicitly expressed, but you also explicitly expressed that ... your obligations under the terms of your PayPal Extras XXXX  account, which includes timely payment of debts incurred. Per my contract and your correspondence my obligation is to pay debts, and NOT a positive account balance of credits you are fraudulently demanding to be valid and claiming to be a debt owed. I asked to provided with proof of accounting, an explanation for the adverse action of deactivating my account, and put them on notice of dishonoring my financial instrument. 
They have also inaccurately accused me of attempting to avoid my debt, when I in fact provided payment. 
On XX/XX/XXXX, I did receive correspondence from Synchrony Bank Customer Service finally acknowledging my notarized Power of Attorney asking for a different version and that I complete a Power of Attorney Certification Form. I faxed a notarized Durable Power of Attorney and the Power of Attorney Certification Form on XX/XX/2023. I also included instructions once again to apply the principals balance to the principals account each cycle for set off. 

On XX/XX/XXXX, XXXX Corporate Specialist of Synchrony bank sent correspondence. He did not provide proof of accounting, or an explanation of why my payment was being dishonored and not applied to my account. He just stated You entered a valid agreement with Synchrony, upon signing the application That does not satisfy any of my requests for lawful explanation of a non-acceptance of my lawful instrument, for proof of actual accounting/validation of the debt, verification of the claim against/signed invoice, a copy of the contract, and full disclosure that my credit was created with my signature. They failed to apply my payment and requested I utilize their preferred method of check, debit card, or money order. 
I asked to be provided with the reason they considered my payment invalid, made them aware that they were dishonoring my instrument and in violation of 18 USC Code 8. Obligation of other security of the United States. They were breaching their contract ( Federal Reserve Act Section 16 & USC ) as a FDIC member by not depositing my financial instrument.This has placed me in a compromising position of having to risk adverse action of late payments or suspension of service, if I do not abide by the payment option they prefer, which is completely unlawful and violates the following United States Codes : laws ( 12 C.F.R. 229.21 - Civil liability and U.C.C. 3-307,103, and 4-106 ).