my phone won't bloody vibrate no matter what. please help
What version of OS?
Try restarting your phone or factory resetting it.
Then take or send your device into a OnePlus service center for a inspection of possible repairs.
i am also facing same problem...for some times...
OxygenOS 9.0.2 based on Android PIE for OnePlus 3 & OnePlus 3T
by Manu J., 2019-05-22