Gaslighted by webafrica

I have been with Webafrica since 2018 and all has been smooth until my move from where I was staying, I stayed at my new place for 2 full months without internet even though I informed them a month prior that I would be moving. Then on 20 February I made contact with them to downgrade my package to 30/30 and the agent assisting me confirmed that this will commence on 1 March. on 5th of March I login to pay my account and I notice the bill is R808 instead of R 520 which is what I downgraded to. I contact them again and the agent LIES and says its because I had outstanding amounts from previous months, I then inform her that I don't have a debit order but manually pay my account on customer zone and I pay the exact amount shown there, she then argues with me and I get annoyed and we don't come to a resolve. Friday 6 March another agent assists me and she informs me that the downgrade was not submitted so she will do it and it swill be effective on 01 April, that's fine but its NOT MY fault, I have confirmation that the downgrade will be effective 01 March!!!! I downgraded due to affordability and I refuse to pay the amount of my previous package!!!!!