Canon EOS-1D X Mark III Advanced User's Manual page 525

Canceling the Pairing
Cancel pairing with a smartphone as follows.
1.
Select [Check/clear connection info].
2.
Press the <
3.
Select [OK].
4.
Clear the camera information on the smartphone.
> button.
In the smartphone's Bluetooth setting menu, clear the camera
information registered on the smartphone.
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