@Camille_P Hi Camille, what was the time format that your co-work was using? Was it dd/mm/yyyy? Also, what was the locale/language setting of the browser?
Normally, if you do not want to throw away local changes, you will need to put the app in recovery mode. This will allow your co-worker to complete the sync. The unsaved changes will not be written directly to the spreadsheets. Instead, it will be saved to a temporary recover folder in the app’s root folder. You can then retrieve the changes from the recover folder and add them to the spreadsheets. You can read more about how to use recovery mode in the last section of this article:
help.appsheet.com - Errors During Sync Errors During Sync help.appsheet.com