Product: Credit card or prepaid card

I had a minimum payment of {$27.00} due on XX/XX/2019. I paid {$27.00} via my online account, deducting from my checking account on XX/XX/2019. This {$27.00} payment cleared my bank on XX/XX/2019. I verified with my bank that the funds had been paid out. I logged into my credit account online to check my available credit on XX/XX/2019. The payment was still pending due to it being the weekend and not a weekly business day. I called card services and spoke with a representative who explained this to me and advised me that the payment would reflect on that following Monday, XX/XX/2019. Once this happened, my available credit limit would update. I logged into my credit account online again on Wednesday, XX/XX/2019 and the {$27.00} e-payment does reflect as being paid on XX/XX/2019. However, my available credit limit had not changed. I contacted card services again on XX/XX/2019 and spoke first with a representative and then a supervisor. Both of these individuals told me that the {$27.00} payment had been received but had not yet been posted. The explanation provided to me was that, because several months prior a payment was returned, and therefore this current payment would not be posted to my account until I gave them permission to contact my bank directly. ( The returned payment was resolved within days of the first returned payment. I also paid the fee due to that occurrence. ) I refused to do so because I felt they had no right to contact my bank to discuss my personal bank account. The supervisor I spoke with stated that unless I allowed them to do so, the payment would not be posted to my account. She stated that the payment may eventually post, at least 14 days from that date, XX/XX/2019. 

I reviewed the credit card agreement online which states : " You agree to pay us in United States dollars. If you pay by check, your check must be drawn on a depository institution located in the United States. If you do not pay the New Balance in full, you agree to pay by your Payment Due Date at least the Minimum Payment Due. You may, at any time, pay the total amount owing on your Account. Payments are posted to your Account in a timely manner as required by law. However, we may delay restoring your available Credit Limit in the amount of the payment to make sure we receive the funds. '' I contacted my bank again to inquire about the credit card company 's demands to have access to discussing my bank account. The bank representative stated that this rarely occurs, only on a 3-way phone call, and that she personally had never heard of it happening for a {$27.00} payment. 

My concern is not only with the questionable delay in posting my payment, which both my bank and the credit card company acknowledge to have been cleared, but also with the fact that the agreement does not put a specific number of days regarding " ... delay restoring your available credit limit ... '' Seemingly, they could delay this restoration for as long as they want. That is extremely worrisome to me. 

I have continued in refusing the credit card company to contact my bank ; to threaten me by stating they will not post the payment unless I give them this permission is absurd. I don't know what else to do with this problem. It has become a much larger issue than just the {$27.00} at this point.