Bad services

I am not happy with vodacom Fibre again. I put in a notice in February to cancel my fibre services. I received an email stating that my services will be cut off end of March. On the 2nd of April I noticed that my services is still running and I called in to report and flag them to cut the services off because I can't be liable for paying for those services. A ticket with reference was only initiated yesterday and tagged as a priority 4. Today I received an invoice showing that I will be billed for April while from my knowledge the services are supposed to be cut off. There is no urgency in closing this matter and I am supposed to move to overseas on Sunday. I can't be rest assured at this moment that my account won't be debited end of April and the worse part is the fact that it will cost me a lot to call in and enquire. This is not my fault at all. Again when I called in today enquiring about the invoice that I received, I was told that the amount charged is for a cancelation fee. I told them that I can't have such a fee because I am on a month to month contract and I gave a month notice to cancel but unfortunately the lady insisted that I am liable for a cancelation fee. Please sort this matter out urgently