Product: Credit card or prepaid card

Without reason,  BP Credit (  affiliated with Synchrony Bank in Florida ) decided to limit my credit line to  XXXX .I questioned their actions and was not given a valid reason within a timely manner. I asked for an explanation as other major credit cards were giving me increases to my credit line. I was not asking for an increase or decrease but their only response was that it had something to do wi th a credit score  - I questioned this as  XXXX  major credit card providers were giving me a higher credit line.     In   XX/XX/XXXX , I made a purchase using this BP  Gas card - They tell me that my transaction/payment is late but then confirmed my payment was in full. I specifically asked them to consider a refund or no late fees as I was told they would be cleared from my account back in   XX/XX/XXXX /  XX/XX/XXXX .      After all of this happening - I wrote a letter to Synchrony Bank informing the bank to close all accounts as I wish to no longer do business with this currupt bank. I pulled my money out of their money market, cancelled other company credit cards affiliated with Syncrhony and then destroyed the remaining half of the credit cards that were in my possession.     Once I recieved all my transferred savings from Synchrony, I wrote another letter asking to confirm all accounts are closed. I wish to no longer do business due to theirk lack of concern, no response, and horrible customer service.     I was then informed in  XX/XX/XXXX  that  I had a pending balance of  XXXX  - I tried resolving this matter as I was told it was a late fee. I tried to explain to both   Synchrony   and  the Debt  Collector that this was suppose to be cleared from my name. The account is closed as they tried decreasing my credit limit with no response to my inquiry.       XX/XX/XXXX  - I  finally spoke w ith a Credit specialist from their debt collection department only to be told - Let 's try to resolve  this issue - Pay the  XXXX  but this will not guarantee resolution of the other debt. I asked why should I pay for a debt that I was told was a courtesee due to my acting upon the original debt I paid - I tried to initiate all communications only to be ignored and now lied to as I was told my account is closed and Paid in Full I refused to pay since the uncertainty of clearing the debt is unknown. I informed the agent when I closed the account, I was at a  XXXX  balance and paid in full with no additional charges. This was back   in  XX/XX/XXXX .
Now, BP ( Synchrony Bank ) continues to bill me for something that I knew nothing abount when my account was closed.     They claim to email me - Not even a formal letter other than a debt collector letter back in  Late    XX/XX/XXXX  telling me I have a pending ba lance of  XXXX  Email is not an official answer - Email me where? You were trying to contact me at what phone number? How is it the debt collector was able to write a formal letter as I received in in   XX/XX/XXXX  and to include a phone call - but yet, the BP Credit company and Synchrony bank could not do this?? With an established Money Market account and other ba nk accounts on file, Synchrony has/had my information on file - It is not that hard to find someone in the system.       Today,     XX/XX/XXXX , this is the FIRST letter I received from BP since  XX/XX/XXXX  showi ng a statement balance and a threat of charging me   XXXX / month  until pay off.