Product: Credit card or prepaid card

Last Fall, I ordered items from XXXX XXXX for delivery and placed the order on my Capital One card. However, some of these items were not delivered, and though it was only about {$25.00}, I decided to dispute that part of the charge through Capital One ( case # XXXX ). That was my big mistake. 

After receiving a letter outlining the numerous steps required to make a claim ( including a demand for a " second opinion '' from another merchant, on its face an absurd request, as no intelligent company will offer in writing an opinion in such circumstances ), I decided to withdraw my claim. I made clear my feelings on these demands for such claims, and said I would be looking to take my business elsewhere when the account was settled and straightened out. In fact, I phrased it this way ; " Please put all legitimate charges back on my account so I may pay it in full and close out this account. I will take my business elsewhere while I decide how to pursue this matter further. '' From this, several months later ( XXXX XXXX XXXX XXXX ), someone decided to close this account, without such a request from me, or without notifying me of any such action. The claim was that even without an actual request for CapOne to close this account, someone did so, months after the letter was received and many more months after the original claim. I only knew this happened because I attempted to use the card and was embarrassed to have the merchant tell me it was declined. 

I called to CapOne 's " customer service '', spoke to Employee XXXX, and was told only then of the closure. The reason given was that I had requested it be closed. I inquired when and how that happened, and only after some time was it claimed that my original letter to CapOne was a request to close the account. I also inquired how Capital One closed accounts, and what information was required in order to perform that task. After quite a few long pauses and some " ummm ... uhhh ... '' I was put on hold so this person could " research '' the facts. I was then told that such information was " proprietary '', and not available to customers. In other words, if someone wants to close an account, we apparently have to guess at what information Capital One needs to perform this task. 
As both this conversation as well as the requests made in order to dispute a claim seem on their very face to be completely absurd, I am writing in search of answers to the following : Can they really require a statement from a third-party merchant simply to dispute a charge? 
I had intended to close this account at some point, but clearly no such request was made specifically in my original letter. How does the CapOne staff see a demand to close an account in the statement listed above or in the original letter? 
If indeed that was a request to close my account, it was made in Fall of last year, and the account was only closed in XX/XX/2019. Why the massive delay? 
Who specifically decided this letter represented a demand to close the account? 
Why was the representative I spoke to in XXXX so unable to answer my questions? I hope you can retrieve the recorded call. I asked her to maintain the call, and for a reference number for the call itself, but was told no such reference exists. 
How will this closure be reported to the credit monitoring bureaus? 
Why can CapOne not provide customers direct answers to direct questions? How to close one 's account should be basic, and have a simple answer. 

I hope you can give this issue the attention I believe such questions deserve. Thank you for your time and attention to this matter, and I look forward to a reply soon.