You receive a transfer on PayPal, Apple Pay, Google Pay or a similar service from someone you don’t know. The amount of this transfer may vary, but will probably be a few hundred dollars. You’ll receive a message after the transfer claiming that it was sent on accident, and the sender will ask you to send the money back. You want to do the right thing so you refund them the “accidental” transfer amount, only to realize later you never received a transfer from them to begin with and now you’ve lost a few hundred dollars or more.
What to do
Do not refund them the amount. Chances are the original transfer they sent you was paid for with a stolen credit card and it will be cancelled on its own. Instead, ask the user who “accidentally” sent you money to cancel the transaction on their end, or request that they contact the platform directly for assistance.