M&T Bank Mortgage Complaint

M&T Bank Mortgage department,

FHA mortgage Loan servicing, payments, escrow account Florida

I was through a some financial difficulties back in the beginning of the year ( layoff ). I was late on some of my monthly payments. I requested a payment plan to my mortgage company which they did and I started paying it off. By the time I sent out my last payment, I was told it was a mistake on the calculation and they needed to get another - and with that I would be up to date including any late fees. I just got off the phone and they said I still owe over - hundred dollars of late charges. Can they keep charging late fees on calculations they made?