Synchrony Financial Credit Card Complaint

Synchrony Financial Credit card department,

Credit determination Maryland

I have a Synchrony Care Credit Card I obtained at a DDS office. I was unsure what balance or credit I had available on my Synchrony card as well as my company provided - card. I mentioned this to the receptionist and was told she could not provide for the - card, but could get the balance available on the Synchrony Care Credit card. She proceeded to call and was given the available balance. Given that, any other card I should call about on my own behalf, would provide information only after I answer multiple pertinent questions to verify my identity. Is this legal??? I was not asked a single question and the party at Synchrony did not ask for my approval for such information to be shared with the DDS office. I called the Synchrony people to question this practice and was told, yes this is information provided to the DDS who is a vendor of services. Any dental, cosmetic service or medical provider, etc. can find out my available credit on this card with no question asked. Can this please be investigated. I will not use this card again if this is valid and/ or legal in any way!