it calls nobody says anything and it hangs up

Calls constantly, then hangs up when answered. Called back & they said they were a security system company. Asked to be removed from call list, then they called 6 times the next day!

how to stop them from calling

Calls and hangs up. I would not purchase anything from a company that uses robo callers then disconnects. Quit calling idiots. May pay them a visit being they're only 25 minutes away, they won't like it either!

I would be shocked if there's really anything there in Decatur. If you ever get a chance to go by and find out it's a legitimate company, it looks like there are enough people on here that a class action lawsuit might be warranted :)