Griffee Dental III PA review: Fraudulent transaction

Dear Sirs,

I addressed to Synchrony Bank with this letter. Unfortunately, the problem is not solved as for the balance in my closed account. Please, help me.
The dental office (Griffee Dental III PA) opened an account on behalf of me.
I signed something (at the very beginning I trusted them) online just for a credit account opening.
I didn’t authorize the transaction in the amount of $746.16.
The transaction was done on 02/15/2023, when I refused of their services completely.
I visited this dental office only once on 02/07/2023.
I knew about this transaction from the letter of CareCredit.
Please, clarify how this transaction can happen, if
• No bill was provided to perform the transaction
• Credit card issued by Synchrony Bank was not applied
• My credit account became available for the dental office
Thank you very much!