I have always paid my CapitalOne XXXX bill on time and in full. For some reason my payment due XXXX XXXX set up via electronic transfer was posted a day late by Capital One. I called Customer Service, spoke to XXXX XX/XX/23 and was told the late fee & interest would be removed from my account. I asked if future interest would accrue & was told that if it did I should simply call & it would be removed. Got my bill due XX/XX/XXXX and, after having paid my XXXX bill in full, received a {$13.00} interest charge. I again called Customer Service to explain that I was told to call if any interest appeared -- and was told the agent couldn't do anything about it. I asked for a Supervisor and was transferred to XXXX. He told me he could remove the charges, but I had to pay the amount of the bill plus the interest charge. I told him that was not what I was told and that I shouldn't have to pay the interest charges. Further, I explained that if they were going to use predatory practices, I would simply cancel the account. He hung up on me. I then called Customer Service again, explained what had transpired, and told them I was going to pay for all my purchases now & wanted my account closed. They refused to do that unless I agreed to their terms which would require me to pay interest until I paid my bill plus accrued interest. I tried to pay my bill on line and it would not let me pay the full amount of my total purchases to date. Thus they continue to lie & steal. They should value the customers who pay in full & not use deception to increase their bottom line. Again, I would like to pay the {$850.00} I actually owe for purchases & cancel my account. I do not need XXXX 's credit card. There are too many legitimate credit card options out there.