Struggling to cancel my wifi at Vodacom

I am currently trying to cancel my Vodacom LTE (30Mps) wifi. I have been trying phoning Vodacom since the 7th of March to cancel. Still no-one has logged that the cancellation has been uploaded. The reason for cancellation is because they have made a change in the contract. They sent out an email that stated the consumer can cancel their wifi before 30 April at NO COST, for which I NOW received a quotation of +- R8000 to cancel the contract. I have again phoned Vodacom, and after that they referred me to various departments, and no one could help me.

Please help. I do not know who to speak to anymore. And I cannot and will not pay for that wifi anymore.