Private or corporate networks often use firewalls or spam filters that can sometimes block certain pages used by Airship. These firewalls use rules that are stricter than a public network.
Try to load the affected page on a different network (e.g. at home) or on your phone when not connected to WiFi (e.g. a 3G/4G connection). If the page loads as expected, then the issue is with a firewall on your corporate or private network.
How to whitelist Airship pages
Your IT department or an IT professional will need to change the configuration of your network to allow the affected domains.
You can get in touch with Airship support on firstname.lastname@example.org to check which domains you should whitelist on your network.