Switch function for table updates based on users

[Justlookinghere]

Hi everyone,

I think this question has been asked before but I couldn't find the proper solution for my problem. For my case, I made 2 separate tables (a table for list of managers and a table for list of employees) and each table consists of list of users which has different roles for my application. I would like these users to have different abilities to update the table based on their roles and at the Are updates allowed?, I inputted this expression:

SWITCH(USEREMAIL(),
User_Employee, "UPDATES_ONLY",
User_Manager, "ALL_CHANGES",
"READ_ONLY")

The expression passed, however, when tested, both users in the Employee and Manager table doesn't allow any Updates, Add neither Delete and it just displayed the data as Read Only. Please advice on my expression. Thank you everyone!