No answers just pay and dont query your account!!!

About a year ago i complained on here about vodacom with the same kind of situation to this day have not explained to me what happened they just suddenly out of the blue gave me a 10k credit on my account after I complained , Recently my account again went up by 10k in one day. I asked them on more than one occasion to email me so that there can be a paper trail because talking to their call centre agents is never a joy. They called anyway but not satisfactory they said that the last time they gave me a goodwill credit after I complained?????? Really! (They never would have given me this credit if I didn't complain) And this time they cant tell me how the account is so high because they don't keep record of url information???? they person was rude. Ive started paying this account which is a lot of money for me but i am upset as I don't believe I owe this money! Vodacom is the worst company Ive ever dealt with. Im not running away from my responsibility to pay the account I just want an explanation. Hopefully they will respond this time.