Vodacom- unacceptable conduct

I have been a loyal customer for Vodacom for years, was contacted and told they are lowering my plans, made t clear that i dont intend to increase my current bill. The quotations for some interactions made in the early fEB ONLY CAME THROUGH TODAY, only to find out all my lines have been migrated to higher plans which means more money for me to pay. This is totally unacceptable and is appalling behaviour, i am disgusted as my bill will be a lot higher than budgeted for. This thing of third parties calling me for upgrades is not sitting well with me.