Any OTG failure please check items below

1.Check if the OTG cable is in working condition (It is recommended to use the official OTG cable)
2. Check  if there is any damage to the USB port
3. Go to "Settings"--"System"--"OTG Storage"(for Android O:"Settings"--"Advanced"--"OTG Storage") to check if the OTG option is enabled.
    Check if the handset has access to root or not, if the answer is yes, please back up all of your data, clear the cache and flash to the latest OxygenOS version.

If the issue can not be solved according to the above steps, we recommend applying for after-sales service.