Account Name Update Restriction

Summary:

For certain roles, the customer wants the Account Name field to be non-updatable.
In the Test instance, we tried using a field-level script in the Updatable condition, and it worked as expected.
However, in the Dev instance, even though the same script has been applied, users are still able to edit the Account Name field.

Is there a way to resolve this, or could it be a bug?

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