Who called from 4072057120

someone from 407-205-57120 keeps calling me then hangs up after I ask who is calling. The are speaking with a very heavy accent. They are calling me at my work number and there is a loud printing machine  noise in the background

They called five times in five minutes, even after I said we weren't interested and they shouldn't call again.

They keep calling i answer noone speaks i say hello hello no one there there call ever five min

THEY HAVE CALLED 6 TIMES IN 2 DAYS. THEY DO NOT LEAVE MESSAGES. SO WE STARTED TO ANSWER THE PHONE WHEN THEY CALL IF WE ARE HOME AND THEY HANG UP ON YOU. THE HAVE CALLS STARTED JUNE 16, 2013 AND WE TOLD THEM WE WERE NOT INTERESTED IN ANYTHING THEY WERE SELLING. SO THE CALLS STOPPED AND NOW STARTED UP AGAIN 10/03/13. IF YOU TRY TO CALL THE NUMBER BACK YOU GET A BEEPING SOUND AND THE CALL WILL NOT GO THRU.

Called me at work...how do they get work numbers?