Hand over clients for systems that don't work

I have on the 18th of June I reported our remote for our tracker system not working and asked what can be done to sort it. Since then no one assisted us with getting the problem resolved. So, we decided not to pay for a service that is non-existent. If Altech can't help us sort our remote to activate our system which we are expected to pay for, then why should we pay. Then we are handed over to a debt collecting agency who calls us dialy and harrass us for payment and add charges for calls irrespective of us telling them our situation. We will NOT pay the fees outstanding as we had NO SERVICE. We will NOT paythe debt collecting fees. Please come and remove your device as we can't use it and please inform your debt collection agency to stop phoning us once twice day. It is ******* to harrass customers for money. Find a reputable firm who complies with legal requirements and learn to jack up your service which has left a bad taste in our mouths!!