Paste "73NQSH9H" into the Zotero search bar in All Fields & Tags mode from the root of My Library. That should show you the attachment that's causing this. There's a forward slash in the filename that shouldn't be there.
Zotero shouldn't have let you create an attachment with a slash in the filename, but apparently that was allowed somehow.
We'll fix this, but for now you'd have to delete that attachment item and then delete it from the trash to allow the sync to go through. (You can make a copy of the PDF first and then add it back.)
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Zotero shouldn't have let you create an attachment with a slash in the filename, but apparently that was allowed somehow.
We'll fix this, but for now you'd have to delete that attachment item and then delete it from the trash to allow the sync to go through. (You can make a copy of the PDF first and then add it back.)