Absolutely disappointing!!!!!

Absolutely ridiculous. I hyad 2 charges on my CC with no authorisation or OTPs. Just someone charging my card but according to FNB CC division i have to get hold of the "merchant" myself and fight the charges. I ask you this,,,, how do i fight with someone that i have no clue who they are. So JA where is the bank security protocols with all these OTPs and dual Verification and online security "????????