ADT not hounouring their Agreement.

My contract started in April 2019 with ADT and when I signed I was promised free 3 Months. Without my knowledge they started debiting my account from April 2019. When they requested admin fee in July 2019, I noticed that they shouldn't have been debiting my account to start with. Several calls were made to the company, I spoke to Vincent and his supervisor Lawrence on several occasions with no luck. I also spoke to the person who assisted me with installation and send them copies of the contract (which they have) to prove that I was promised free 3 months of services. Since July 23 until today I have received no assistance from the company and everyone is too busy to resolve my query. I have two accounts with the company but I have already lost any hope of good service with them.