Product: Credit card or prepaid card

I contacted Capital One as soon as the charged amount accrued to let them be aware of the situation. I disputed the charge right away. Capital One filled the dispute using the wrong code and then later told me that they could not and would not change it. 
I am not disputing the charge all together ; I am disputing the amount of the charge! I believe the merchant violated a couple different guides in the charging process and Capital One would not even look at the factors of the merchant! They initially charged back the amount and provided me with a letter stating the documents I needed to provide them with. I did that and then they said that I needed to provide a letter from another company in the same industry which is a car rental company. No car rental company would provide me with any such statement as they said that I am not a customer of theirs and it would be a risk liability for them to make such statement. I reported that back to Capital One and then they told me that I could not dispute the charge further without that statement. 
A couple different dispute managers at Capital One was extremely rude and unwilling to even let me speak. I asked Capital One if I could send this to pre-arbitration and was told NO! I do not feel that I was treated fairly by them as a cardholder. 
1st of XXXX requires merchants to identify each authorization as a final, pre-auth or undefined. Final and undefined authorizations will be valid for 7 days ONLY, otherwise a new authorization will need to be obtained. And pre-auths are equivalent to incremental authorizations and will be valid for 30 days. The last time that any type of charge, pre-auth, or authorization was ran by the merchant was XXXX and the max it was ran for was {$810.00}. The next charge was only XX/XX/2022 in the amount of {$9500.00}. 
The issuer is responsible to ensure that the chargeback is submitted for the correct reason code. When I told Capital One that they disputed the charge with the wrong code they refused to correct it. 
I requested that it be sent to pre-arbitration and Capital One refused to let me. 
I also wanted to file XXXX Goods or services not provided. Since I bought the additional insurances that covered damage or theft 100 % - and then the rental company would not allow me to use it- buy stating that I simply just did not return the vehicle until a month and a half later is a complete and outright lie and they are using that to defraud me! The services and insurance that I paid an optimal amount for was not available to me when needed. 
Specifically under the CAR RENTAL MERCHANT DISPUTE MANAGEMENT GUIDES IT STATES : o The merchant is required to obtain authorization on ALL transactions, therefore ensure proper authorization has been received between the time the car was rented and return is crucial. It says the merchant needs to keep a record of all authorization amounts and approval codes associated with the rental. The total amount authorized must be within 15 % of the actual transaction amount if the actual transaction amount is more than the allowed variance and additional authorizations required for the difference. In the event a decline or other non-approval response is received request a different form of payment. Ensure authorizations are process properly. Since I had a $ XXXX credit limit and they waited 45+ days to charged me {$9500.00} I am sure that this is not acceptable. 
Transaction Processing- Transactions processed as a result of a loss, theft or damage are not valid and should not be completed. 
Proper Disclosure- The cancellation policy needs to be disclosed to the cardholder at the time of reservation. I did sign the rental agreement and it does not state on there anything regarding theft of the vechile. More to the point it stated that in case of theft the customer would not be charged. 
Bottom line is that Capital One is not providing me, the cardholder, with the assistance that I need and all throughout the process Ive felt as if they are representing the merchant. 
Please help me. I am attaching my rental agreement, XXXX optional insurance statements, and other relevant documents for your review. Thank you in advance for any assistance you could provide to me. It would be greatly appreciated!