tubesock gem is not able to listen on the port of sinatra application

I have a sinatra application running on a port 7095.When I have added code mentioned in https://github.com/ngauthier/tubesock#rack and run puma code,tubesock gem does not listen on 7095.

I have used following in config.ru

run Server.new
run Sinatra::Application

When I run following I get the following error

const socket = new WebSocket('ws://dfr101.com:8096');
undefined
VM222:1 WebSocket connection to 'ws://dfr101.com:8096/' failed: Error during WebSocket handshake: Unexpected response code: 404

Thanks