The installation file check at the very beginning of using bisq is not working

As shown in the help video on the bisq page, I wanted to check the file with the programme from the www.gpg4win.org page. But that did not work. At the end, the following message appears:

Does anyone have an idea where the error could be?

The message says that the data cannot be verified. I have just checked the help video again and it says the same thing in the check result. It seems that my check on the PC worked, because it gave exactly the same result as in the help video. But why is the file considered correct when the message is: The data cannot be checked?

grafik

Gpg tends to alert when a key is not trusted by other keys, giving unclear messages.
I’m not sure because I’m not familiar with German or gpg4win, but that’s something to consider.