Discover Credit Card Complaint

Discover Credit card department,

Payoff process Florida

I am making efforts to pay down my credit card by paying more than the minimum balance. For the last few months I have been monitoring my bills. There is a one month delay between paying down the highest balance ( cash advance ) and it appearing on the bill. When I receive the bill, I am being charged interest on the balance that is shown - before the pay down - and not the actual balance. I have made several calls and have confirmed that the money payed beyond the minimum charge is going to this higher balance. However, when I ask about why I am being charged interest on the amount before it was payed down, I get no clear answer and no one will confirm that the interest charged in on the new, lower balance.