PayPal - send the money back please

[Thelatin]

When someone sends me money via PayPal, and asks me to return it, what are they doing?   I’ve had a regular for years that does this on occasion, they pay the fees.   Where is this money coming from? 
 

They aren’t scamming me.  Are they scamming someone?

[BuffaloKyle]

It sounds like they are hiding money from someone. Like they are getting money in a USA bank account and then they send it to you. Then you send it back and they deposit it into an overseas account.