Capital One Credit Card Complaint

Capital One Credit card department,

Florida

Charges to my credit card in excess of the available balance are being approved rather than declined. I contacted the bank to see about changing this and seems I can not. There is no charge for going over the limit, but I do not want my account to be able to go over its limit. If the account is over limit during a statement it will get reported and effect my credit score. The account was not always this way and it seems some recent change I dislike but seem to have no control over.