private AdditionalInfo ValidateProperties(AdditionalInfo additionalInfo)
        {
            if (additionalInfo.Event == null)
            {
                return(AdditionalInfo.Empty());
            }
            // Assign properties
            additionalInfo.Event = Context.CheckCenterEvents.Find(additionalInfo.Event.Id);

            // Do not overwrite existing entities
            Context.Entry(additionalInfo.Event).State = EntityState.Unchanged;
            return(additionalInfo);
        }