Error 18

The washing machine decided to throw up an error today (at a most inconvenient time of course).

A quick Duck Duck Go (alternative to Google without the snooping on you) revealed the problem and solution. This was removed from the pump, since the hairs are too dark and too long to long to be mine, and I haven't used any cash since before the pandemic the pound coin wasn't mine either. So do I return the pound to my son or keep it as a tip?