NoMethodError: undefined method `current_sign_in_at' for #User:0x000055ce01dcf0a8 by using Devise_token_auth rails gem is not working

I had this issue recently and it turns out I didn't have the trackable fields in my migration. There are two ways to fix this:

Option one. Add a new migration that adds the trackable fields to User

## Trackable
t.integer  :sign_in_count, default: 0, null: false
t.datetime :current_sign_in_at
t.datetime :last_sign_in_at
t.inet     :current_sign_in_ip
t.inet     :last_sign_in_ip

Run rake db:migrate

The second option: run a down migration

Start with this command - add your migration version number

rake db:migrate:down VERSION=xxxxxxxxxxxxxx

You should then be able to add the trackable fields to the migration file and then run

rake db:migrate up VERSION=xxxxxxxxxxxxxx

Run rake db:migrate