Looks like the date of at least one observation you’re trying to sync has an observed_on date of December 24, 2021, so that’s what’s causing the syncing issue. However, an observation like that shouldn’t be allowed to save. Can you please open up the observations and send screenshots of them either here or to help@inaturalist.org so we can take a look? Specific details like exactly how you made the observation(s) would also be really helpful.