What this sounds like more than anything is not being strict about your syncing. It’s especially hard to keep 3+ devices in sync, so you have to be absolute about it.
- Sync when you open the app AND when you close/leave the app, on every device every time.
- Don’t have changes happening in multiple devices at the same time.
Since it seems like they are out of sync right now, you’ll have to do a full round of syncing to get them caught up. You choose what order you want to do them, but sync device A, device B, device C, and then device A again.
I can allow space for their being more complicated reasons for this (especially around add-ons), but try strict syncing habits for a bit first and see if the issue pops up again.