I have heard it said when you get scam phone calls, play along with the caller as long as possible, but provide absolutely no information about yourself or anything. The idea is to keep them on the phone. The longer they are on the phone with you, it's costing them money for the phone service, and it's less time they can scam someone else.
I really like the idea of giving the phone to your 4 year old child or grandchild. You might play musical phone also, put them on hold, anything to keep THEIR line timed up as long as possible.
Thanks for the "heads-up!"