Now I am very worried that we can't complete the community canter, but we are already at the end of fall, so it would be hard to restart.
I'd suggest you to make screenshots of what bundles you have done (and partially done), then type "regenerate_bundles" in the SMAPI console on the host machine (whoever of you who have the farm save file on the computer).
This command will respawn all bundles, but you would need to fill them all again. For this I'd recommend you to use "CJB Item Spawner" mod, which you can find on Nexus Mods. Then stop time and refill your bundles according to the screenshots you made. It will take about 30 minutes to do so, though.
This way you will have no issues if you have completed bundle but it still wants more items.
If you encounter this issue again - use the workaround that "Caio Fabricius" found on this thread - it will take literally 5 minutes to fix, though you will be forced to restart a day - so I'd suggest to do this on the morning of the day you plan to fill bundles.
Also it would be better to use Notepad++ for this, because save files can be massive.
This bug always duplicates "/{NUMBER}" before "</string>" so you would need to delete them.
Like if you have "0/4/4" - then delete last "/4" to make "0/4".
Or if you have "0/3/3" - then delete last "/3" to make "0/3".
In my experience bundles that are most likely to get damaged are: Fall Crops, Quality Crops, Fall Foraging, Winter Foraging, Exotic Foraging, River Fish, Field Research, Chef's.
I named them exactly as they are stated in the save file, so it would be easier for you to find them.
Playing on English can be a workaround for this issue, but if you are not familiar with the language - then it would be for the best to save it for the last resort.
Currently this bug is marked as a milestone for the SMAPI 3.14.0, so possibly after this update it will be okay to stop worrying about this issue.