what does this mean?


That's very strange that it is telling you that. I looked at the game without an engine and it clearly was a forced mate in two. I also did a deep analysis and it told me the same thing. Stock fish will simply say mate in x amount of moves when it's forced(deep analysis below)

Thankyou for posting the game Colingohmann98. i didn't knew how to post the game and neither could i figure it out. That very weird stockfish giving him +1 advantage

no problem! to post games all you need to do is click on insert diagram/game and then copy and paste the pgn from the game(pgn code appears when you click on the download button below any game online)

that's a bit more complicated you can download stock fish 8 from the website itself but you need a chess system to run it on. If memory serves downloading this as well should allow you to run the stockfish file.

I don't know what the problem is here. When I put the final position into stockfish it says it is mate in 1 for white. And that is indeed the case.