Non-nullable property 'ActivationCode' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Message' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'AdTitle' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'AdSubject' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'CategoryName' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'TutorName' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Subject' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Title' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Description' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.