Token should not be created if a user is already signed in and already has a token

     def create
     
        field = (resource_params.keys.map(&:to_sym) & resource_class.authentication_keys).first
        
        @resource = nil
        if field
          email_value = get_case_insensitive_field_from_resource_params(field) 
          @resource = find_resource(field, email_value)
        end
       
        if @resource && valid_params?(field, email_value) && @resource.active_for_authentication? #this return true
          debugger
          valid_password = @resource.valid_password?(resource_params[:password]) 
          if (@resource.respond_to?(:valid_for_authentication?) && !@resource.valid_for_authentication? { valid_password }) || !valid_password
            return render_create_error_bad_credentials
          end
          debugger
          @token = @resource.create_token
          @resource.save
          sign_in(:user, @resource, store: false, bypass: false)    
        
          yield @resource if block_given?
  
          render_create_success
        elsif @resource && !(@resource.active_for_authentication?)
          if @resource.respond_to?(:locked_at) && @resource.locked_at
            render_create_error_account_locked
          else
            render_create_error_not_confirmed
          end
        else
          render_create_error_bad_credentials
        end
        
      end