Error 'Could not find concurrent-ruby-1.1.5'

[Samuel van Eck]

I've recently done a bundle update of my Gems. Now when starting guard with bundle exec guard I get an error message:

Could not find concurrent-ruby-1.1.5 in any of the sources
Run bundle install to install missing gems.

I've checked my Gemfile.lock and it's present:
concurrent-ruby (1.1.5)

I've deleted all of my gems, Installed bundler again, done bundle install but still it keeps failing.

When I checkout of my branch which had the bundle update everything is fine and no errors are present.

I don't know what is going on. Do you have any advice?

I've added my Gemfile and Gemfile.lock as attachtments

Gemfile.lock.txt
Gemfile.txt

[Samuel van Eck]

Figured out what caused my specific issue:

Because we are using Docker I had to do a rebuild of the Docker environment.