So, i've got a little problem with this card.

Normally you get this card from a Tavernowner in Velen if you win against him
but i have won against him, the game said "you get this card" but its not in my inventory or in my deck.

Great. I reload and the same thing... i won, get the message and thats it... no card, nothing. Best Part, you can't play a second time against him.

Is this a Bug or am i too stupid?

remember some cards are for certain factions only.
Did you check all 4 factions?

Yes, when i press [ESC] and click on the Gwint Menu, then i see all my poorly 31 Cards... it doesn't matter which fraction i choose all i got are 31 cards, before the fight and after

then you must not have picked up any faction cards, weird.
The cards on the left are the cards you own that are not in your deck, maybe you have to scroll down to see them all.

You are the best... it looks like this card belongs to the Nilfgaard-Fraction and it was all the way at the bottom...
Thank you very much :)