Unable to generate Item numbering using startswith

Summary:

I am trying to generate item numbering using with String function "startswith" as shown below:

Primary IF Expression - startsWith("9", [Item].[Eng].[PART Number])

Secondary IF Expression: True

Return Value = "10000" + [Item].[Engineering].[PART Number]

(This part is working)

Secondary IF Expression: False

Return Value =auto_sequence("NonOSPartNumber", 10001000000, 1)

(This part is NOT working)

Implementing Product Management (23D) states that "Returns TRUE when look_in_string starts with look_for_string. Returns FALSE otherwise." Not sure why FALSE is not working.

Can anyone provide me pointer why this is not working?

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