Synchrony Financial Credit Card Complaint

Synchrony Financial Credit card department,

Advertising and marketing California

I signed up for CareCredit card to pay for dental expenses with no interest if paid on time. I was on auto pay so as not to be late or miss a payment. I was charged more then $74.00 in interest. Care Credit said the 6 month period was just a promotion. Why would I sign up for a credit card that charges 26.99 % interest, I already have a regular credit card with 14 % I would have used that? Dental offices, etc. promote this card as a way to pay for medical expenses not covered by insurance, easing the financial burden by having free interest for 6 months. It was presented to me as a way to pay for my dental expenses interest free always as long as I paid each bill on time and within 6 months.