Telkom Upgrade Without Permission

Telkom upgraded my business fibre speed and package at a higher cost without permission. I've tried to get it reversed but am not getting any help. The billing deoartment can't help and refer me to sales downgrades and the person I spoke with was unhelpful and hasn't actioned my request to revert to the previous package. Much of my time and cell phone costs have resulted in no help from Telkom and I don't know how to proceed.