Does the obscuration bounding box cross out of the location filters for the project? It looks like it is close to a coastline. If any area of the obscuration box is outside the locations included in the project filters, the observation won’t be included in the project.
Assuming this is the issue, there are many threads addressing it on the forum, including:
https://forum.inaturalist.org/t/defined-places-collection-projects-and-obscured-observations/27396