easy one
Cool mate in 3!
I see that the Ke6 is not forced but played out through the other alternative Ke8 then Qg6 would be alternative pushing king back to Ke6 or risking checkmate with Rf7...so worse is perpetual check until white brings in second Knight...
The only alternative the king can do also leads to checkmate... This puzzle is correct, even it is not a forced mate in 3, it is mate in 3, or maybe the player can delay it to mate in 5 depending on the move.
Here is a fun puzzle of a game I played...