Hi Hamid,
a server used by your plugin is down and there is no way to connect to a tour with other devices and video/audio does not work.
In console it says cors-error but I guess that's due to them being down.
Code
Access to XMLHttpRequest at 'https://rtcmulticonnection.herokuapp.com/socket.io/?userid=...' from origin 'https://...' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
https://rtcmulticonnection.herokuapp.com says "Offline for maintenance".
How can my clients manage to use this plugin again?