Delayed or Missing Notifications on Find X9 After Updating to ColorOS 16

What’s Causing the Issue?

Community feedback suggests that the behavior is linked to:

• Tighter background app restrictions introduced in ColorOS 16

• Aggressive battery optimization routines

• Temporary performance slowdown as the system re-indexes files after a major update

One user noted:
Since this new update came out, all apps on my phone are working very slowly.

These symptoms indicate that certain apps may be prevented from running freely in the background, resulting in delayed push notifications.

How to Fix Delayed Notifications

Try the steps below to restore normal notification behavior:

1. Disable Battery Restrictions for Key Apps

1. Go to Settings

2. Tap Battery & Performance

3. Select App battery management

4. For essential apps (WhatsApp, Gmail, Instagram, etc.) → set to No restrictions

This ensures the app can run in the background without being closed by the system.

2. Recheck Notification Access

1. Go to Settings

2. Tap Notifications

3. Select Special app access

4. Tap Notification Access

5. Ensure your important apps are allowed

This step ensures apps are authorized to receive and show notifications properly.

3. Check for System Patches
Go to: [Settings] > [System] > [Software Update]

If OPPO has released a patch or optimization update, installing it may resolve the issue immediately.

4. (Advanced) Enable ANR Monitoring

If you want to diagnose app suspension:

1. Go to Settings

2. Enable Developer Options (if not already enabled)

3. Tap Show all ANRs (App Not Responding)

This helps identify if apps are being force-stopped in the background.