calls all the time never leaving a message or hanging up right after an answer. very rude and annoyng

Called my workplace where I am a receptionist. I answer and do the opening routine. No response, so I repeat myself in case they didn't hear me. Then I hear a cough and they hang up.

The original debtor told me that the Federal Trade Commission and the BBB Are trying to prosecute this Fraudlent company but they keep changing their phone number. They will get them eventually, Do NOT send any money to them!

I answered and a womans voice said "Hello". I said yes and then she disconnected the call....

Not sure who it is but they call my cell phone today when i anserwed it they hung up tried to call it back busy for an hour then when i got through when it was not busy no one anserwad the call! Would like to know if they got the wrong number or if they are prank calling me this has happened on my home phone far too many times and my old cell phone to the point i changed my cell phone number last year and i don't want to have to do that again!