Thank you for your response. I’ve been able to further isolate the issue — it appears that only iOS devices, including iPhones and iPads, are unable to access the site.
Thank you all for your help! I’ve figured out the issue — it was because my domain was not registered with the authorities. After switching to a domain that is properly registered, everything is now working!
Am I guessing correctly that you are trying to access your platform from China? Do new websites typically need to be declared to authorities, such that they are white-listed?