Unable to get camera and microphone for jitsi meet module

Hello. I am new to android development. Please help me to get permissions for microphone and camera for a module in humhub - jitsi meet.
 It uses camera and microphone. But when I try to use it through app, it shows no permission given to the it. 
When I myself grant the app permissions, from settings, then even it does not work.
 Please help me.