"CNAME is already taken" error for .fish domain. Maybe an edge case bug?

I have the domain lo.fish.

Tried to set it up as the custom domain for my github page but got the following error instead:

The CNAME lo.fish is already taken. Check out https://docs.github.com/articles/troubleshooting-custom-domains#cname-errors for more information.

Look through all my repos and don’t see it being used.

Doubt someone is actually trying to use this domain.

Maybe a werid bug for speical cases?

Couldn’t remember if I have used it previously. Could be a cache thing too.

Would be nice if I can use my domain asap. Thanks!

this is the repo for the gh pages: https://github.com/CAST3LLA/lo.fish/

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