We want to validate the start date of employee's address in business rule - validation not firing

Summary:

We want to validate the start date of employee's address in business rule - validation not firing

Content (please ensure you mask any confidential information):

We have created a validation rule for Me —> Contact info to validate that the effective start date of any new address is a Monday date (for payroll purposes).

We have created a business rule and it is not firing as expected.

This is our first time creating a business rule with advanced logic (needed to capture if the address effective start date is a Monday) - so not sure if we are missing something there or elsewhere.