this is a collection company for sprint    they call night and day   leave no message   let the phone ring once or twice then hangs up    i called the number back and she refused to tell me what they wanted until i verified my ss    well she gave me the ssn last four digits to verify  turns out they are debt collector for sprint. i had cancelled cell service with sprint a long time ago  got married two years ago and new land line is in married name and unlisted. told her that acct was canceled and i owe nothing to take me off the list and asked how they got my number  she said we have access to all numbers or something along that line. told her to take my number off their list then hungup.