IdentityLookup fails to filter an SMS the first time it's received.

Number:rdar://51249377 Date Originated:30/05/2019
Status:Open Resolved:
Product:IdentityLookup Framework Product Version:12.3.1
Classification:Bug Reproducible:Always
IdentityLookup API is failing on iOS 12.3.1. Even after passing `.filter` action it still allows the SMS. (It was working correctly on iOS 12.3)

This only happens the first time an SMS from a particular sender is received. Any subsequent .filter action work as intended. 

Steps to Reproduce:
1. Open the attached
2. Build and Install the app to device and enable filter extension from
3. Send any SMS from an unknown number.
4. The first time an SMS is received from a particular sender, it will fail to get filtered. Any subsequent SMS from same sender will get filtered correctly.

You can repeat this test by deleting that particular sender's SMS thread and sending SMS again.

Expected Results:
The SMS should be filtered and moved to the SMS Junk section of

Actual Results:
The SMS is allowed.

iOS 12.3.1

iPhone X 64Gb.

Additional notes: 
This is the same issue as reported previously in radar #42417770. It was previously fixed but has regressed somehow in iOS 12.3.1.


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