Pawn to f5 glitch

This has happened to me multiple times. I have my pawn at f7 - Move it to f5 when I have an opposing pawn on e5. I should pass the attack and sit beside right? That is what I see on my screen. Then the e5 pawn attacks to f6 - takes my pawn that was not actually there! Just cost me a game... Anyone else see this? I am there a lot as I use the Hungarian open... HELP!

https://www.chess.com/article/view/his-pawn-cheated-and-killed-my-pawn

 That was VERY helpful - thank you.

I don't know if that's sarcasm or not, but I'll take it as sincerity.

 The good news is, en passant is the last trick move in chess. Assuming you understand castling of course.

Acheron - absolutely sincere. I went to Wikipedia and read about En Passant... I have not used it yet but I have avoided it - can't wait until I can try but it has not presented yet. Thank you for the link.

Drew