Hi, please use our thread for inquiries related to FreeFlarum so that I can find it next time and we stay organized, thanks
gnfb I wonder if this has something to do with it
Using a root/naked domain
Yes, the library that we use to resolve CNAME doesn't support using CNAME with root, and it's not officially supported by DNS either. There's nothing we can do about it, sorry
So you're redirecting www.4um.xyz to https://www.4um.flarum.cloud? The 4th domain level doesn't work at FreeFlarum, and even if it did it's not what you want. Redirecting just takes you to https://www.4um.flarum.cloud, and since that doesn't work, it shows an error. You need a CNAME record
This CNAME is likely what you want. Replace <TTL> with your own, e. g.: 1 min.
CNAME www 4um.freeflarum.com. <TTL>
After that, go to https://freeflarum.com/settings/forum_settings and in the "Custom Domain" box, type www.4um.xyz. If everything went okay, you should be notified with a green success text. Since browsers cache DNS and domain settings in order to speed up page loading, you might need to test if you domain works in private browsing/incognito mode, or another browser