Rule based attribute is blank

Summary:

Rule based extract attribute is blank though the formula is showing data in logs

Content (please ensure you mask any confidential information):

We are experiencing a strange behavior with a Rule type attribute in one of our custom extracts.

It is a simple formula that calls ValueSet and the value is returned by formula. In the extract log, I can see my log statements have the value. The same value is being returned. The data types of attribute and return value also match. I tried by having just one statement to return a simple string like 'Test' and that doesn't show in the extract xml too. I also deleted the attribute and recreated it, but no luck,