Issues adding domain for iCloud email

So no guarantee that this will help, but for me, I had to go back and remove the quotes (like they recommended) AND change their recommended TTL setting from what they suggested to my hosting's default (HostGator).

The 'quote' thingy worked for me as well for 1 domain.

After this I added another domain, but it keeps telling me that mx record is not valid.

For al those with same issue and this fix is not helping:

I contacted Apple Support. They also could not fix it for me. The escalated this to the engineers. Now I'm waiting for their response.

You’re welcome!!

This worked for me. Thank you!