The guy on the phone used obscenity

Received hang up in voicemail.  Number blocked.

Recorded message left saying "Your call is very important to us. Please stay on the line and you'll be transferred to the next available agent" -- as if I called them -- and music played for one minute, then call terminated.

No message left :-(

Exact same thing happened to me.  I stayed on the line to ask them to take me off their list and they put ME on hold with music after I answered the phone.  Then the recording said Goodbye.  Weirdest darn call!