MTA-STS not loading

I keep getting the below in my nightly emails, but I’m not finding a way to resolve this issue.

STS policy fetch for domain ‘[domain].com’ failed with error:
STS policy fetch for domain ‘box.[domain].com’ failed with error:

I’m not sure if there is a script I should run or there is something else.
I shouldn’t be missing any DNS records as I’m aware
If I go to mta-sts.[domain].com it loads the Mailinabox page.

My DNS is hosted external since I am hosting other services on the domain, as well.

I wonder if part of it is I don’t have _smtp records, acccording to this thread

My admin page does nto generate these records in the External DNS page. I’m not sure what I am missing.