SyncAdapter's periodic syncs abandonned

Question

I have an application where I use SyncAdapter to collect some user data and send it to my server (activity tracking application that synchronizes the data with server periodically). I have set it to work every 4 hours and everything was fine. However after 2-3 weeks of running the application, suddenly I have realized that syncs weren't performed for 2 days (on some devices even longer). I have checked the adb shell dumpsys content and I didn't find there entry for periodic sync of my application. Earlier the entry was looking like that:

JobId: 102971, MyApp u0 (com.my.package), com.my.package, PERIODIC, reason: Periodic, period: 14400000, flexMillis: 576000
owningUid=u0a307 owningPackage=com.my.package

Now there's none.

Tell me please if it is possible that Android for some reason cancelled my periodic sync?

This problem was encountered on Samsung Galaxy S7, S8, S8+ phones, so it may be Samsung-specific issue.