shows mistake but there is no mistake

i finished one game and it said there was one mistake
however when i go to review it show there is no mistake

is this what it is supposed to say or is it a bug?

When you finish the game, that is a shallow analysis. Once you actually review it the engine does a much deeper analysis.

So you won't always see the same thing between the two images.

ok thank you

Also I've noticed that these game reviews don't usually line up with the lines from the engine when you select "show lines". Half the time they aren't even in the top 3, so honestly I wouldn't go off that and just go off the engine lines - if you gain points after a move then good move, if you lose points you made a mistake. 

thank you both of you

yeah that's right.