Contract degraded without my permission

I upgraded my contract in beginning of 2017. I was on one of the top packages. 01/01/2018 Vodacom decided to downgrade me to a cheaper package. I have been struggling with them until 16/02/2018 to give me an answer why this was done and to put me back on my previous package. 3rd complaint in one month. I also struggled with a sim swop and that took 9 days. The service is so terrible I do not want to do business with them further.