The 2-factor authentication and the backup function of the Ledger Nano S Plus do not work via a mobile number.

- The 2-factor authentication on Ledger devices is typically done by a combination of PIN entry and manual confirmation of transactions on the device itself, without the need for a mobile number.
- The backup function is based on a 24-word recovery phrase, which you should write down and keep safe when initialising the device. This phrase allows you to restore your cryptocurrencies to a new device if the original device is lost, stolen or damaged.