Called and hung up. "Number is not in service" according to Verizon.

Called my house twice yesterday.  Made mistake of answering second time (was expecting another call).  Big mistake.   There was silence - after I yelled "Hello?" several times, there was an eerie bleep and then a female robot said "Goodbye" and then it disconnected

I fear that this was a call to see if my number was valid. It's blocked now - but I doubt it will call again now that my number's probably been shared with other scammers.