Ruby on rails 4 ActiveModel:：禁止活动管理员中的属性错误

我有一个模型，它只在active admin中创建。我有以下控制器设置：

def index
@events = Event.all
end

def new
 @event = Event.new
end 

def create
@event = Event.new(event_params)

结束

我的事件模型是：

class Event < ActiveRecord::Base
 has_one     :trainer, inverse_of: :events
 belongs_to  :training_request, inverse_of: :event

 delegate :module, to: :training_request
end

有人知道为什么会这样吗

值得一提的是，在rails控制台中，它保存得很好。

  controller do
    def permitted_params
     params.permit event: [:venue, :trainer_id, :description, :training_request_id, :title, :date]
   end
  end

在ActiveAdmin.register事件中执行

Parameters:

{"utf8"=>"✓",
"authenticity_token"=>"H0sdhO3JsWBb8tYvFm52YvGsVvcnArigaVD+1r5HzL8=",
 "event"=>{"training_request_id"=>"3",
 "venue"=>"this is a venue",
"description"=>"this is a descripton",
"title"=>"event title",
"date(1i)"=>"2018",
"date(2i)"=>"3",
"date(3i)"=>"5",
"date(4i)"=>"05",
"date(5i)"=>"00",
"commit"=>"Create Event"}

  controller do
    def permitted_params
     params.permit event: [:venue, :trainer_id, :description, :training_request_id, :title, :date]
   end
  end