Rails: "Could not find bundler" (2.2.11) required by Gemfile.lock. (Gem::GemNotFoundException)

Make sure you're entering "bundle" update, if you have the bundler gem installed.

bundle update

If you don't have bundler installed, do gem install bundler.

I had this problem, then I did:

gem install bundle

notice "bundle" not "bundler" solved my problem.

then in your project folder do:

bundle install

and then you can run your project using:

script/rails server

ruby-on-rails ruby rake bundler

I had the same problem. This worked for me:

run rvm/script/rvm and also add it to your .profile or .bash_profile as shown in https://rvm.io/rvm/install/
use bundle without sudo

CodeHunter