Cancelled Contract

I take out a cellphone contract two years ago...which expires END April... I phoned Vodacom to make sure this contract is cancelled end April and they told me no it is End May.....My contract expire end April and if they listen to the phone records between me and Vodacom when I spoke to them about all my contracts expiring dates and the number which contract end was also said end April.. Even on my Vodacom App it shows contract end 30 April... I refuse to pay an amount end May as this contract end April... I can't understand Vodacom.. Look like the employees is not really trained. I don't even think that I will ever take out a contract with Vodacom....Understand better when people telling me to go to another company as Vodacom just give problems..