master failed to start

Facing an Issue

Deploying a Rails 5 App with Capistrano. Deployment Fails while trying to start Unicorn with thus error message

 master failed to start, check stderr log for details

The Same Error, if i start Unicorn with this command

bundle exec unicorn -D -c /home/deploy/apps/app_production/shared/config/unicorn.rb -E production

Details of unicorn.log

bundler: failed to load command: unicorn      (/home/deploy/apps/app_production/shared/bundle/ruby/2.3.0/bin/uni  corn)
LoadError: No such file to load -- zip ...

Installed Ruby(2.3.1p112) User wide with rbenv.

Any help in resolving this would be appreciated.

Thank You