With the Nuki app you can reset your Opener to factory default settings. All data will be permanently deleted. After the factory reset you can set up your Opener again.
There are two ways to reset your Opener to factory default settings:
1) Via the Opener settings To reset your Opener via the settings, tap on the desired Opener in the Nuki app and enter the settings. Choose "Manage Opener" and then "Factory reset". Then follow the instructions in the Nuki app.
2) Via the help section You can also reset your Opener if you do not have it in your Nuki app. Open the Nuki app menu (top left) and go to "Help". Select "Opener factory reset" and follow the instructions in the Nuki app.