I have another Joplin sync-related problem, but this time it's on mobile.
What happens is nothing syncs whenever I open my mobile app. I do get notifications on my desktop saying that there were changes made to timecheck .txt files, but there's zero syncing going on and I don't see any changes or recent additions to my notes/notebooks. Usually this process takes just a few seconds.
I'm using a OnePlus Nord CE 2 phone running Android 13. Joplin version is 2.11.32. Syncing via Dropbox. Sync on desktop and tablet works fine.
First, double-check that there aren't two Joplin folders on Dropbox (e.g. Joplin (1) and Joplin). If there are, it's possible some devices are syncing to one folder and others to another.
I have only one Joplin folder on Dropbox, and I have the latest client version for mobile and never changed my device's time/zone and date. I missed the part about checking sync status though. I got impatient. LOL
What I did eventually was clear both my device data and cache; and then set up the app, encrypt, and sync everything all over again. It worked, and syncing is ongoing.
I hope this doesn't become a regular/recurring problem with Joplin. I love this app, and I depend on it for both work and personal matters and projects.