Repeated unwanted, unsolicited calls.  When picked up, caller hangs up then calls back approximately 1 hour later.  Who is this?

its collections for shaw direct

recd the call from RO inc looking for person whom is not here anymore but i asked for name and phone # as i could give a message to the person. the gentleman said he would call back so i advised him they would not be here as they moved away so he then hung up on me .i called back and the computer please advised me to stay on line while it accessed my account.

I answered the call with hello.....moments later a female voice is saying she is away from the desk and I could leave a message!  Like HELLLLLOOOOO.....they called me!  Why would I leave them a message when I don't know who they are and they just dial my number but don't care to speak when I answer.......weird or what!  Plus annoying....too bad these people couldn't find something productive to do with their time, like clean cell walls in prison or something!  LOL