Contract problem

I have a problem with vodacom i had 2 contracts *** and *** and i have paid off the *** and requested to be closed and move the number to prepaid however for whatever reasons they decided to close both numbers and i logged the service request to re open the *** with reference number *** then today they have close the case and re open the number that was suspended but they added 3more months on my contract and no one at the service desk is prepared to assist me all the consultants they transfer me from one department to another now i received an sms telling me that i need to pay R****.09 on the 15 May 2020 and no one at Vodacom is willing to assist i have paid for my services so i dont know why Vodacom is doing this... Thank You