Try the following:
Reload the page to refresh it. Press Shift+F5 for Windows, or Command+R for Mac. Alternatively, click on "reload page" at the top of the address bar, or highlight the URL so it turns blue, and then press Enter.
Log out and log back in. Log in from our website unioo.dk (do not use the invitation link once you're registered). Read more here.
Check your internet connection. Ensure you have a strong internet connection. Problems can arise if you're using a public or work network. Try logging out of this network and use your phone’s Wi-Fi instead. Alternatively, you can share the internet from your mobile (hotspot) to your computer.
Switch device. Try using your mobile phone or tablet instead of your computer, or vice versa. Or borrow someone else's device. Read here to learn how to help each other.
Change internet browser. Read how to do this here.
Open an incognito tab and try inside it. In Chrome, you can find incognito under the three dots in the top right corner of the browser.
Restart your computer/phone/tablet.
Update your operating system if system updates are available (check under "Settings").
These tips are generally good advice for when technical issues arise, so keep them in mind for your future use of digital tools.