Cancellation Request

I am honestly not happy with ADT and how my matter is being handles i requested to cancel my contract with them and the consultant who is handling my case is no longer Responding I have been calling since last week and every time they tell me she is not at her Desk meaning they paying her to not be at her Desk . My issue is ADT claims that i have signed up for a contract of 36 months with them But they are not able to Provide proof that instead they email a blank contract that does not have my Initials nor my signature on the Terms yet i am told that i will need to Pay R4500 for Cancellation i am not happy and will not accept this i need urgent assistance with above