Synchrony Bank Consumer Loan Complaint

Synchrony Bank Consumer Loan department,

Installment loan Managing the loan or lease Managing the loan or lease California

I have been regularly paying my Synchrony Bank bill. The account balance at the last statement was $840.00. I went to pay today and I have $3400.00 in interest charged this month. They told me the 0 % interest came due on -/-/15 and if I do n't pay the $840.00 off, I will then be required to pay this extraordinary amount of interest. I had no idea this would happen and am at a loss. Is this legal?