@drespectpl Hi there, and thank you for reaching out to us on the forums about this. I'm sorry to hear you're getting this message. This message is indicative that you are experiencing an authentication error.
An authentication error usually occurs when you are logged into the wrong Ubisoft Connect PC account while launching a game. As a first step, please make sure you're logged into the correct Ubisoft account. If you do not know or recall what account the game you're trying to launch is on, please reach out to our Support Teams via our Support Website, Twitter DMs, or Facebook PMs, with a screenshot of the following file location. >>
C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher\cache\ownership
Please also include a screenshot of your proof of purchase of the game from Steam that you're trying to launch.
If you're contacting through Social Media, please make sure to also include the username and email address associated with your Ubisoft account. Our teams there will have to link your account before you're able to upload your files. Thank you!