Useless ISP service

I have been trying for 6 weeks to downgrade to a smaller package to no avail. I signed into Mweb self help and was only allowed in to an area where you can't do anything the other area is restricted and you must enter an OTP sent to your phone which never arrives. next I tried to phone them and again for the call you get asked for an OTP sent to your phone, again never arrives. The above I tried numerous times to no affect. I contacted their agent on Facebook and he asked for my details and said an agent would contact me. the agent did phone me and as I mentioned downgrade he transferred me to the same number as when you phone in asking for an OTP again. BACK TO SQUARE 1