S...Hamster is correct. If you're pm the Do Not Call list, then any solicitation call me get is certainly a scammer.
Ignore or string them along, as you prefer, just don't give them any real information.
As to needing to give traceable information before getting a number, unfortunately that's not the case. There are lots of ways to get a fake ("spoofed") number to show up oncaller
... on the Do Not Call list ...
... show up on caller ID so it makes them hard to stop. Also, they're often overseas and beyond the reach of U.S. law enforcement.
I wish I could have better news.
Good on you!
I like stringing these jerks along, too.
Only comment I would add is that they don't have any database about actual credit card balances; they're just calling at random or in sequence to see who "bites".
You can make up any numbers you like and it'll be all the same to them ....