Paying for something that has ended yet apparently in thier system it shows that it’s only ending next year..I have provided them with my contract but nothing has been done

I have a contract with mtn that I took in 2019 wich it was for 24 moths so it was supposed to end in July So I consulted with mtn four months back about the ending of my contract but they said it’s only ending next year which it’s not true...they asked for a proof of contract wich I did provide them with it but nothing has been done up to this day I have been in contact with some lady who works in kwaggafontein but recently she’s been rude and yet still I need to pay again for something that was supposed to be due in july