Why does it say the option is not available when enabling a card reader?
If you're being told that the option isn't available when trying to enable a card-reader, it usually means a card-reader hasn't been ordered for the Digital Banking service you're logged into.
You will need to order a card-reader then wait 2 working days before trying to enable the card-reader you have.
Alternatively you may be eligible to use your biometrics on your mobile app.