This number was used firstly on my cell phone with no message. One minute later it called my house line. No message again. Who is this?

who is this

Called but no message left on voicemail. Probably a scammer.

Received a call at home and then my cell. No message left.

Called both cell phone and home phone at the same time. Cell and home phone are with two different carriers, and in different area codes so no real connection .  No call forwarding either. As I hung up on one the home phone rang.  Most likely some boiler room fraud artists running multi autodiallers.