Domain Mapping - Error Message

Hello,

So I'm trying to use the domain mapping feature but as of the moment, It's not allowing me to map the domains. What happened was that, I added the domains that I need to map here: https://my.wpengine.com/installs/nextlevelblogs/domains and then, I went to the dashboard of the site that I added and tried to map it from there, but it's not working. This is the first time that this happened, the others are already working... and I made sure that the DNS were already pointed to mine. Any suggestions on whatelse needs to be done?

Domanin name is unavailable to access.

We can't access your new domain. Mapping a new demains can take as little as 15 minutes to resolve in some cases can take up to 72 hours, so please wait if you just bought it. If it is an existing domain and has already been fully propagated, check your DNS records are configured correctly.

I already checked and they are configured correctly.

Let me know. Thanks.