Hi,
Have you checked the vibration settings in ''Settings > Sounds and Vibration > Vibrate while ringing'' and also ''Vibration intensity'' and ''Vibration pattern,'' you didn’t say?[br]
If they’re all OK try [https://www.technobezz.com/how-to-wipe-cache-partition-on-samsung-galaxy-a30/|wiping the cache partition] and check, in case it is corrupted cache data that is affecting the vibrate somehow.
If still no good try starting the phone in [https://www.hardreset.info/devices/samsung/samsung-galaxy-a30/safe-mode/|safe mode] and check.
If it works OK in safe mode then a ''downloaded'' app is the cause of the problem. The tricky part is to find out which one is the culprit. You will need to uninstall each ''downloaded'' app, one by one and test the phone in normal mode between each uninstall to see if it works OK. When it does then the last ''downloaded'' app that was uninstalled was the cause of the problem. A ''downloaded'' app is one that you ''downloaded'' and installed in the phone and was not pre-installed on the phone when you first got it.
If still no good, perhaps the vibration motor is loose or faulty.
Here’s an image taken from a teardown [https://www.youtube.com/watch?v=G_eixkTpL_8|video] for the phone showing the location of the [https://www.crazyparts.com.au/vibrator-for-samsung-galaxy-a30-a305.html|vibration motor], that may help, (supplier example only to show part and what it may cost).
[image|2442078]
(click on image to enlarge for better viewing)
If the vibrate motor is faulty there are other suppliers online that may suit you better. Just search for ''Galaxy A30 vibration motor'' to get results