An invoice is for something that has to be paid, a receipt is for something that has already been paid. Are they asking you to pay, or confirming that you have paid?

Either way, let's hope you never clicked on anything in the message.

Did the message come through your normal mail, or is it in your actual Ebay messages?

How would you like Ebay to deal with it?

Ebay has no control over fraudulent messages sent by scammers outside of the Ebay ecosystem.