`bundler: failed to load command: thin (/app/vendor/bundle/ruby/2.2.0/bin/thin)` on Heroku

[arslanaly47]

Ruby: 2.2.7
Rails: 3.2.21

In my Gemfile, I have: gem 'thin'

Everything goes as expected on local, but when deployed to Heroku, it says:

Using rack adapter
bundler: failed to load command: thin (/app/vendor/bundle/ruby/2.2.0/bin/thin)
Heroku::API::Errors::ErrorWithResponse: Expected(200) <=> Actual(400 Bad Request)

I have been working on this problem for the past 5 hours, but still unable to get any solution. Is it a compatibility issue?

[Deacychen257]

me too