Attemping to use AVMutableComposition always returns nil in LockedCameraCapture extension

I am creating an locked camera capture extension that allows you to take a video with an overlay image on top of it. I'm using AVMutableComposition in order to achieve that. It works perfect in my main app, but when initializing AVMutableComposition in the locked camera extension it always returns nil.

Is this expected?

Attemping to use AVMutableComposition always returns nil in LockedCameraCapture extension
 
 
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