Problem when updating data using _THISROW?

[hapham]

Hi everyone! I am having a problem as follows:
I have 3 tables as follows:
A faculty can manage 1 or more classes.
A class can have 1 or more students.

FACULTY

• ID Faculty (text type)
• Faculty name

CLASS

• ID Class (text type)
• Class name
• ID Faculty (Enumlist-Type Ref FACULTY)

STUDENT

• ID student (text type)
  Student name
  Student phone
• ID Class (Ref type CLASS)
• Faculties support (Enumlist type Ref FACULTY) → Have Initial value: LOOKUP ([_ THISROW]. [Class ID], “CLASS”, “ID Class”, “ID Faculty”)

Now I want to filter so that faculty who are logged in can only see the students of the class they manage. Hence, I use the [Faculties support] column for filtering. Employees on that list will be able to see.

Everything is normal, when the user starts to enter students. But the problem occurs when the user changes [Class ID] to the new value this [Faculties support] column does not update itself!

Can anyone help me with this?

Thank you very much!