DNS resolution for hhs.gov

[Samuel Jackson <bobin.public () gmail com>]

I wanted to run this by everyone to make sure I am not the one losing my
mind over this.

A dig +trace cob.cms.hhs.gov fails for me as it looks like the NS for
hhs.gov does not seem to resolve the hostname.

However dig +trace cms.hhs.gov resolves and so does dig +trace
eclkc.ohs.acf.hhs.gov

However if I simply ask my local resolver to resolve cob.cms.hhs.gov, it
works. Any thoughts on why this is the case?

Thanks,