So anyway I decided to buy Far cry 4.So I made my first account on UbiSoft connect(i never played any other Ubisoft game). Got the game key, when I submitted my Key, the Ubisoft Connect just suddenly crashed and the next time logging in I didn't found any trace of my bought game.
Hello Inzilo_, welcome to the forums!
Sorry to hear about your experience. After checking this for you I noticed that the key has been activated within the account. However, this key is for additional content (Season Pass) and does not contain the full game, and that would be the reason that you are unable to see the game within your account. In this case, I would recommend checking with the seller if the key has been described as a full game or additional content that requires a full game.
I hope it helps and if you have any additional questions, please let us know.