I have added a column for UserType on user's table.

I have referenced User table on Unit table.

I have added a LookUpScript on UnitsRow as shown below:

```
[DisplayName("Lecturer"), NotNull, ForeignKey("[dbo].[Users]", "UserId"), LeftJoin("jLecturer"), TextualField("Lecturer")]
        [LookupEditor(typeof(UserRow), FilterField = "UserType", FilterValue = UserTypes.Lecturer)]
        public Int32? LecturerId
        {
            get { return Fields.LecturerId[this]; }
            set { Fields.LecturerId[this] = value; }
        }

```

UserType is of type enum, as shown below:

```
[EnumKey("SmartAttendance.UserTypes")]
public enum UserTypes
{
    [Description("Admin")] Admin = 1,
    [Description("Lecturer")] Lecturer = 2,
    [Description("Student")] Student = 3
}

```

However, when I go to add a new unit/edit an existing one the dropdown is empty. I have 3 users in the database and one user is of type UserTypes.Lecturer

Please advise what I am missing.