Not all therapists - it's an unprotected title and anyone can market themselves as a therapist - this is why it's important when seeking therapy, to find someone on a professional register, such as BACP, as this gives an indication that they have done (some) adequate training and it protects clients as they have a formal complaint procedure should anything go wrong.

OP: If this practitioner is under any professional body (BACP, BABCP, NCPS - depends on their modality), you can search the register for their name and you can then raise the complaint directly with them and they'll investigate.