Strange things happen... Loss on the next day? No guys!?

Alright. I am not sure how this could happen, but we will look into it!

Thank you. I'll appreciate!

The point is: did you actually hit abort? Did you hit the little button with an X on it which says "abort" when you hover over it?

The point is: changing the result of a blitz game 24h later is strange.

Are you really not willing to answer a simple question? It seems as though you simply do not want to admit that it wasn't the site's fault, but yours. If you don't press "abort," that means the game won't abort and your opponent can make a move at any time he wishes. It's your own fault that you left the game before ending it, so you deserve to lose it.

But that's not what happened. He canceled the game and his rating didn't change. He won his next game and his rating went up and then a couple hours later his rating gors down.

Yeah, the game was played Thursday evening and current losing streak lasts from Thursday 7pm to Friday 4pm.

The only explanation I have: the second but last game has been declared "lost" a whole day after the last won. In fact I have no winning streak of "1" but a losing one. The last game was a win though.

Can you tell me what happened on Friday where everything was ok in the morning and in the afternoon changed although I did not play on Friday?

Here's what happened: your opponent saw the game from Thursday was still ongoing and you had made a move, so he thought he might as well reply. Then, since you had left the game behind, it prompted the player whether he wanted to claim a win or call the game a draw, and he obviously took the win.

Well, actually I thought I had cancelled the game properly ("abbrechen"). I had never experienced any problems when doing this in case of no response. So a blitz game can be open for days?

Obviously, it is possible that there's actually a bug involved here, but it seems rather unlikely to me. Also obviously, if you did hit the abort button, the game should've been aborted immediately and shouldn't have caused any rating change. I don't think there's a time limit on how long a game can last for, (even without a move having been played) so it seems perfectly possible that a game stays ongoing for a day.