If you are unable to view your website's content from a specific network it can indicate that the network has been configured to use an internal DNS structure.
If you're experiencing issues viewing your content, try accessing your website from your smart phone, while the smart phone is on your carrier's mobile network, not your wi-fi. If you are able to view your website successfully, this may mean there is an issue on your office network. Visitors outside of your office's network should be able to view your webpage just fine. If the internal DNS structure has a specific record entered for your domains that isn't matched to the records listed in Content > Content Settings > Domain Manager for your connected HubSpot domains, the request from your website browser to the hosting server (HubSpot's server) will not be able to complete.
To verify whether your network is using an internal DNS configuration you'll need to reach out to your network engineering team. If your network does use an internal DNS structure you will need to pass that team your HubSpot assigned CNAME records from the Content > Content Settings > Domains Manager and have them update the records in their configuration. Your IT Team may also need to flush the DNS cache.
If you are the IT administrator for your network, check out this resource for instructions on flushing your DNS cache.