/clear @a item 0 0 not working all the time

Build: Publish #344189
Impact: Breaks the game unless the client restarts and spawns in netherstar
Repro Steps.
1. /clear @a [item] 0 0. Connect the command block to a hopper clock and then to another command block that outputs text
2. Unload area
3. Save and exit
4. Rejoin and see if it detects.
5. Repeat steps until break. When this happens log in and out and the problem will be fixed.
Observed Results:
Detecting of item doesn't sometimes.

Video provided. Second video in drive too big to upload.