Invalid auth token on production site

I get this error

Invalid auth token

on my production website (Rails 4) deployed using capistrano and puma. Just that error on a white screen and nothing else. How do I debug this?

I googled for similar error but all of them are dated and deal with browser specfic issue with Safari but for me opening the website in any browser gives this error.

config.secret_key_base has value defined.

the website works fine on development mode.

You my friend did the same mistake as I did, and specified path tp pumactl.sock instead of puma.sock, right?

Thanks for this, exactly what I did...