Oauth facebook with ruby on rails 5.2.5

Question

Since two days i tried to make Login with Facebook on ruby on rails using devise but it returns me NULL as email's value. I read many articles on stackoverflow but a lot of them are from years ago and none have worked for me. Thanks you for helping.
Here is the message in my console when i choose my facebook account

Answer 1

def self.from_omniauth(auth)

unless auth.info.email
  auth.info.email = "#{auth.info.name.split(' ').join}@facebook.com"
end

user = User.where("email= ?", auth.info.email).first
puts auth.info.picture
puts auth.info.name
puts auth.info.email
if user
  return user
else
  where(provider: auth.provider, uid: auth.uid).first_or_create do |user|
    user.email = auth.info.email
    user.password = Devise.friendly_token[0, 20]
    user.name = auth.info.name   # assuming the user model has a name
    # user.image = auth.info.image # assuming the user model has an image
    # If you are using confirmable and the provider(s) you use validate emails, 
    # uncomment the line below to skip the confirmation emails.
    user.skip_confirmation!
    user.uid = user.uid
    user.provider = user.provider
  end
end