Product: Credit card or prepaid card

My XX/XX/2020 Capital One credit card statement indicated a new balance of {$1200.00} was due by XX/XX/2020. On XX/XX/2020 Capital One received my payment of {$1200.00}, which was {$10.00} underpaid due to clerical error by my office manager. 

On the XX/XX/2020 Capital One statement there was an interest charge due on purchases in the amount of {$18.00}. I did not notice the interest charge on that statement because frankly I always pay my new balance amount in full every month. The new balance due on the XX/XX/2020 statement was {$2000.00}, which included the {$18.00} interest charge and the {$10.00} outstanding balance. 

On the XX/XX/2020 Capital One statement there was another interest charge, this time in the amount of {$9.00}. I noticed the interest charge on this statement. On this statement it indicated that Capital One had received my payment of the full balance due on the XX/XX/2020 statement in the amount {$2000.00} on XX/XX/2020, a full two weeks before the due date. 

I spoke to both XXXX and her supervisor XXXX at Capital One today, XX/XX/2020 to discuss the interest charges on my bills. They agreed to waive the interest charge of {$9.00} which appears on my XX/XX/2020 statement, but not the {$18.00} interest charge on my XX/XX/2020 statement. 

My view is that Capital One 's practice of charging {$18.00} for one month 's interest on a {$10.00} underpayment is abhorrent and usury. This was not a late payment circumstance where the customer missed the due date. In fact, the payment was received by the bank on XX/XX/2020, a full 10 days before the due date. Aside from the fact that the payment was underpaid due to clerical error by {$10.00}, the bank had 10 days to send an email or a text to me to advise that my payment was underpaid by {$10.00} and to avoid interest charges please remit the {$10.00} before the XX/XX/2020 due date. I receive emails and texts from Capital One periodically when they suspect a fraudulent transaction on my account. But when they have the opportunity to expropriate fees from my account in the form of interest charges they are mute. 

I also object to the practice of charging interest on the whole balance rather than the {$10.00} underpayment. This is a usurious practice that should be illegal. I owed {$10.00} and they charged me a total of {$27.00} over two monthly statements. That is annualized interest rate of 1600 %! 

And to add insult to injury, XXXX stated that he would " adjust '' my grace period so that I would not be charged interest on my XX/XX/2020 statement too. I questioned him how I could be charged any interest on my XX/XX/2020 statement when I paid the {$10.00} underpayment on XX/XX/2020. He said that the bank can charge interest for two successive months after a partial payment notwithstanding the fact that I had paid my underpayment of {$10.00} on XX/XX/2020. 

I have not read the small print in my Capital One agreement because it is boilerplate language that I assumed had protections for the consumer based on federal consumer credit laws. I am shocked that the bank could charge me {$18.00} interest for a {$10.00} underpayment on my next credit card statement and another {$9.00} the following month even though I had paid the {$10.00} underpayment. 

The organized crime doesn't charge these rates. I have never paid late on this account, nor paid less than the full amount due since I opened this account except for the {$10.00} clerical error. I am shocked that the bank did not waive the excessive interest charge for the month of XXXX. I will be also shocked if they are allowed to charge me such an egregious amount. Finally, I take solace in the fact that the month in which my payment was {$10.00} underpaid due to clerical error was not one with a significantly larger new balance.