When you reach the extraction wizard in the workflow you see the “Connected Devices” screen, then connect the device.
If you see that the device shows as Android Generic (with the green Android logo) or a set profile (with device picture) it is ready to go, if seen as a “?” or a “magnifying glass” proceed to step two.
Turn USB debugging off and on again as certain devices turn off USB debugging when the device is connected or disconnected, so make sure it is still turned on.
OPPO AND OTHER ANDROID DEVICES
Look in the Additional Settings Menu. Under the Safety/Security/Privacy menu under the heading of Device Administration, check to allow unknown or similar sources.
Change the USB mode on the device by pulling down the top notification bar of the device and see if you see MTP/PTP listed. If so, press this and switch between the different modes. On certain devices some modes work better than others. Some devices do not have MTP/PTP mode and may have transfer files or similar.
Note: USB Mode could be in the Developer Options Menu under networking USB Configurations.
Lastly, go into Developer Options and see if you have an option to Revoke USB Authorizations. This usually acts like a trust protocol to the computer and can act up from time to time. Press this and see if you get a prompt on the device to trust the computer.