Capital One review: Checking and credit card payment and returns

Back in Feb 2021, I paid on my Quick Silver Card, a few days later the payment was return. So I paid it again, the payment was return again. I contacted the card rep and was told that the payment was stopped by my Bank account, which is my Capital One Checking. After a few days of back and forth, the card service team set up a 3 way, no one could figure out what was going on, so an investigation was ordered. Soon after that I made a payment on Platinum card and that payment was returned, this went on as did the first card did. So another investigation was enacted on this card. A few weeks later I got a letter insisting that I pay on these cards, I did and those payments were returned. We set up another 3 way and I insisted that the charges be suspended until the new investigation revealed the Capital One was having with my payments. I also suspended the auto pay feature on my accounts. A few time to cancel auto was over ignored and payment was applied anyway, I insisted that they be reversed. Then Capital One started sending harsh texts and emails, now I've received letters canceling my cards. This is unfair customer service. Thank You