Domain Mapping no longer working corectly

The primary domain setting is no longer working.
Example URLs:
Primary Domain: http://www.andrewhowell.realtor
Secondary Domain: http://www.lambtonliving.com

When I try going to the primary domain its redirecting me to the secondary domain... And takes a really long time to load..

Also when I went into the domain mapping section for this subsite it said that both of these domains were invalid for some reason. Nothing has changed with the domains (that I am aware of).

This is also happening to other subsites on my network...

Can you help me troubleshoot this?

I have granted wpmudev support access.