Uptime reports domain as not public

I’ve tried activating Uptime through both the Hub and Hummingbird. It will show as active for a short time in Hummingbird, but then disables and re-enables randomly.

When I try to activate Uptime through the Hub, I get an error that the domain is not a public domain. I’m using Sitelock security and my CNAME for my domain points to their servers.