Cannot start Syrinscape Fantasy Player

Hi, I have a similar problem. Syrinscape gets stuck in the loading screen. I tried uninstalling it, logging out, installing an older version, restart the laptop, unblessing every device…
I also tried to install the App on my phone and was able to log in and use the app normally so it seems to be a problem with my laptopn I guess?
It would be great if you could help me out please.

Windows? What version?
MACOs?

Oh, sorry. I have Windows 10.