Synchrony Bank Credit Card Complaint

Synchrony Bank Credit card department,

Billing disputes Florida

RE : CARE CREDIT CARD, - 2014 I had to have -. dental work and the dentist office signed me up for a Care Credit Card for the $8600.00. bill. They said I would have no interest for a year promotion. To date I have paid $ - balance and when I went to check statement, I found out that they accrued 12 months of interest for the entire year -- at 26.9 %! Putting my balance back up to $8300.00.!! I am shocked at this deception and of the $3000.00. I pd means nothing now. I read that there was a class action lawsuit about this, I called Care Credit and they were no help. I feel I have been unfairly taken advantage of and have no way to keep paying this dental debt as my pmts have increased as the entire balance back to near original amt! Please advise on how to get reimbursed via class action lawsuit. This was never explained to me, the dental girl said no interest for a year as a promotion special. I need advice quickly please.