If you are in a hospital or clinic with a network firewall it's possible it is blocking access to websites or ports used by Doxy.me to make a successful call.
To ensure you can make a successful call please ask your network admin to 'whitelist' the following:
All of the above, and open UDP port 3478 for inbound and outbound traffic to *.opentok.com and *.tokbox.com.
You can also run some diagnostic tests to help identify the issue.
If you are still having trouble, please email firstname.lastname@example.org