If there are errors in connecting to a network or the Internet, it may help to reset the network settings on the OnePlus smartphone.

This will reset the following network settings:

Note: Resetting the network connection settings will delete all stored data and settings such as wireless passwords.
It is not possible to restore.

Android 10 | OxygenOS 10.0
Step 1:  Open the  Settings
Step 2:  Tap on  System
Step 3:  Tap on  Reset options
Step 4:  Tap on  Reset Wi-Fi, mobile & Bluetooth
Step 5:  Tap on  Reset settings
  1. Open the Settings
  2. Tap on System
  3. Tap on Reset options
  4. Tap on Reset Wi-Fi, mobile & Bluetooth
  5. Tap on Reset settings

OnePlus Instructions