error after making custom authentication

I used to have the custome authentication and everything ok. I tried to make custom authenticaion using email instead of username and it worked in development but when uploaded to heroku i get the following error:

I did makemigrations and migrate in development and with heroku. Strange thing is in heroku when i create a superuser it will ask for email address as expected then it gets stuck!

Note: I didn’t have this error in development mode!

please help.