You upgraded dependecies for gem omniauth-oauth2 to "~> 1.3.1" but not update version for gem omniauth-paypal
f052deb#diff-8b7db4d5cc4b8f6dc8feb7030baa2478R5
In my project after bundle install showing that
add_runtime_dependency 'omniauth-oauth2', '~> 1.2.0'.
Please do this