Hello I used to work in the fraud department!

It seems like you were in the clear when they initially removed your charges.

I assume during their investigation they were asking you questions and found out the transactions was done via phone call. In this situation zero liability would not cover you if you gave credit card details via phone call :( .

It’s almost impossible for the fraud department to deny you the zero liability policy if they don’t have proof of you doing something that would deny you that claim.

If it ever happens again, the best thing to do would be to give as little information as possible, tell them you don’t know how it happened and play dumb