Firebase Custom Domain Verification fails

As the title says, trying to verify my custom domain with firebase fails.
I just want to change my firebase emails to use my custom domain instead of firebase.com
I followed the instructions, added the CNAME and TXT entries and waited several days, but it failed twice.

which custom domain is this regarding? that would be good for us to know.

is this the instructions you are referring to?

Sorry I should have been more detailed in my description. I bought a domain (icmd.app) on uniregistry and successfully changed the domain name server to netlify, so far so good. Now I am using firebase for authentication, but the email they are sending is using some ugly link with firebase in the title. There is the option to use your custom domain, when you verify that it is yours. Now Firebase shows you some TXT and CNAME entries that you should add, which I did using the netlify dns panel, but after 1 day Firebase still failed to accept the verification.

Hey @ndistqt,
When I run host, I see the TXT files you set up:

$ host -t txt icmd.app
icmd.app descriptive text "google-site-verification=hGbEBSKOimStK46dHZaHt8PrIyuUMHkS4zmWLWGh9sE"
icmd.app descriptive text "@"
icmd.app descriptive text "firebase=icmd-b7117"

I also see the CNAME records in your DNS panel, in our database, and upstream at our DNS partner. I’m afraid this is something you’ll have to get Firebase support for, but if we can help with anything else please let us know.