Due to the nature of the service, your host or a security plugin could block the Solid Central IP. If this happens, you may need to whitelist it.
207.246.254.118
Solid Central requires access to the site in the same way a user would access it, and that means that you’ll need to make sure not to block things. One common way (especially for sites under development) that needs extra configuration is HTTP authentication. If you are using basic HTTP authentication to hide a site, you’ll need to add a specific allow line for the IP address of the Solid Central servers, to bypass the additional password.