Faulty tracking device

Disappointed with Matrix's Beame unit - I had a working unit in my car until the battery ran out - I was then advised that the unit had to be replace. Twice I took the car to their fitment centre to have the unit replaced (which was done) but ever since the unit does not pick up the location on the app - the third attempt was that a technician was sent to my house to replace the unit - it worked for an hour and back to death...