Talking to these folks at all is a bad thing as it acknowledges someone is on the other side of the line and gives them the opportunity to sell your number as an active number to other scammers.
this is absolutely correct.
on the other hand if you've already spoken to them then you may likely already have flagged your number as 'active'. if so, there is little to lose by having some fun with them. i like to keep them on the phone for a long time and holding conversations specifically designed to make them feel awkward. always assert that you are not eekzues but rather a friend/family/lover; then consider talking points:
- that eekzues has recently passed away and how the scammer sounds like such a nice person you just need to talk to them about it
- question whether eekzues was cheating on you with the scammer; make bold claims and demand to know where they were at various odd times
- let them know "the job is done" and that you "need the cash and plane tickets as promised"
- consider asking them what their favorite flavor of edible underwear is; see how far you go with that
i've had a lot of fun at the expense of telemarketers. they make owning a phone less comfortable so the least i can do is repay the favor.