Doubled and Inaccurate Billings

Doubled Billings I moved in to a 2 bedroom apartment in a complex in Pretoria East in Feb this year, I have until now only received 2 accurate bills from Impact since I moved in, and my bill seems to be increasing to almost double every month, I am receiving bills with inaccurate overdue amounts plus my usage has somehow gone up to double the amount since June, I do not understand how this is possible as I live by my self and and during the week I leave my my house at 08 am in the mornings and get back only by 7 or 09 pm most nights. Since my first inaccurate bill containing ridiculous overdue amounts, i have been trying to get a hold of them but if I phone the number provided on my bill for Pretoria East, I simply get an answering machine, if I follow the prompt to speak to a consultant, I hold and simply end up at the answering machine with the same prompts again, I have also mailed them at ***, where I simply get an electronic reply/ticket with no means to an end. Now as far as I understand, they are also closed to the public. so HOW am I to resolve my issues with them if there is NO WAY of physically communicating with them??