Fix my account vodacom

got a statement that my account is with the collection department. I am very confused because I cancelled this account a few months back and settled the amount they wanted. Now they say I owe R950. of which I don't understand as it was a small amount that I was paying monthly which was R45. Then they said I was in error with R188 and paid it and I asked then to close my account they said for closure I should pay R367 which I did. Now I'm very confused and worried. I am not working. How will I pay the R950 of which I don't know where it came from? Please help. The lady who was assisting me after I have paid she said the account is closed unfortunately I forgot her name. Please vodacom rectify and close the account as is affecting my credit record. I paid what they told me I owe. Now have sent them several emails on their subscriber email but no response and no one has got back to me. Vodacom is messing with my financial state.