keep ringing and do not leave a message

Several calls in past week, but never close enough to see callerID, today was different, so searched the number and landed here.
Wouldn't it be great if these scammers could put their time into doing something good?

Scammer

Called me 3 times now im in nz cant even understand there voicemail

Scammer

Annoying

fraud

Rang whilst at work in car, they didn't expect there were 3 other people in car with me whilst on car speaker. Great fun to string along

Caller: Nielson Market Reseach

Media Survey

keep ringing but hanged up while I answered

Caller: Kantar

Media survey

Keep ringing, when answered just hangs up, if not answered does not leave a message