So basically I was doing tactics on the tactics trainer, (who doesn't) and I came across this question.
https://www.chess.com/tactics/27497
https://imgur.com/a/Pg391
The thing is that I played Qxd2 which was the correct answer, after Qd2, but when I clicked to see the "correct" answer, it recommended Nxc2??? hanging a queen. Even the engine agrees!
I did the question again and then, instead of Qd2, the computer played Nd2 and I was getting confused now.
So I refreshed the page and went to the recent puzzles and click on it. The question was right this time, BUT now after Qd2, my queen went missing!
https://imgur.com/a/Pg391
(Second Picture)
The third time I did it,
https://imgur.com/a/Pg391
(Third Picture)
well, it says that Nxf2 is the answer again!
I've also reported this question.
Browser: Google Chrome Version 63.0.3239.84 (Official Build) (64-bit)
Computer: Asus A541U i7 7500U
State: Few Months Old
p.s. When is the new board coming? I've been waiting for a long time