Approval not triggered for change in "Registration Number" for Suppliers

Summary:

Hello,

I have configured an approval workflow in "Internal Supplier Profile Change Approvals" where it is supposed to trigger an approval whenever a change is done on any field at Profile and Address level.

However, we noticed that for certain fields the approval does trigger but when changes are done in Contacts Tab, it is saved automatically without triggering an approval. For example, when Phone number is changed as shown in the attached screenshot.

Is there any attribute that can control change in Contact Details?

Regards

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