Interest charges.

If you do not pay the balance due each month in full, you will then have interest accrue on your outstanding charges. For example, if your balance due for December 31 was $200, with a minimum payment due of $50, and you pay $125 that month, you did not pay off the balance due. Yes, you paid more than the minimum but not the whole amount due. Therefore, interest is now charged.

You'll get interest charges if you carry a balance. You should check your payments to ensure that you are paying the balance due, and not the minimum payment.

Without seeing your statements (don’t post those here as we’re all just users like yourself) there isn’t much more guidance the community can provide. I’d recommend reaching out to support for details.

Support isn't helpful. I continue to get charged interest for paying off my full balance, and they can't explain why.