They dont want to cancel my contract

I am a contract customer with *** number it is due to expire on the 17th of this month.i started speaking to the last month about not renewing my contract, I first called as per refference *** and was told that a request for cancellation has been sent. I then called mid month to confirm I spoke to sidwell nyember as per refference number *** and he told me that there is no need to give written notice for cancelation they will cancel it. I then decided no let me give them written notice, I then sent it.now I was first told that I am a loyal customer they dont want to loose me but I told them I no longer wish to have contract. Now im told to wait for 90 days before cancellation as to why I dont know because the contract expires on the 17th and im not expecting them to continue give service to me and I no longer use the number I told them. It must be cancelled with immediate effect on the 17th.