ROBBING AN MANIPULATING CLIENTS

I switched from afrihost dsl to fibre around april, but only recently I noticed they have been billing me for the dsl line as well as data from may up until Now! I have tried several times to sort this out with them, but they seem to be carefree regarding this. I was told by one service agent in an email that I would be refunded and also not billed for November as in the below email,

"I have requested management to credit the DSL data package from May & to credit/stop the November invoice. This credit will be used to offset your future bill." Today I received an email saying this: " there will be charges for the month of November service as well. Unfortunately, we are unable to credit the charges as the service is still active on your account." I have CANCELLED YOUR SERVICE!!!! I JUST WANT MY REFUND!!! Afrihost is super sharp to take your money and sell you new services without clearly stating things to clients and also continuing to bill me for a service I obviously cannot still be using since you are the ones who upgraded me to Fibre!! this is stupid and I cant believe I have to fight like this to get my money back. Its disgusting, I dont want to be with a company that operates this *********ly.