Adt has failed to deliver the service paid for

I contracted ADT to supply me security systems for which they promised to installed few days after payment. Payment was made and its been now 3 weeks of calling and not been helped. Every time I call, they send me from one person to another. On three occasions , I asked to cancel everything and asked for the payment back and they suggested I drop them an email to which they have not responded to. When I call the sales consultant who was helping me, he does not answer my calls. He pretends to always be busy. Now I found a debit order amount double the agreed on monthly fee on a date prior to my pay date that I told them. Please help if possible. Am too frustrated and I want this service terminated asap. I don't want them to even install anything as we can't agree on anything so far. They just don't Want to listen to me.