Worst customer service ever

It is impossible to get customer service. Every call I make is either cut off and I am sure it is on purpose or put on hold for 8 minutes until I need to cut the call. I have upgraded and now my thumb print does not register so after driving after the delivery guy I cannot receive my device. It is impossible to cancel my contract or get any help. I was told by a customer care consultant to go a MTN store to register my thumb. They don't do that. On my 20th call currently to no avail