Why are the codes generated by my Mobile Authenticator app not being accepted when I log in to IBKR?

Use IBKR Mobile Authentication (IB Key) for secure two-factor authentication when logging in. If you are an existing IBKR client and have already activated IBKR Mobile Authentication (IB Key) via IBKR Mobile, you do not have to take any action. Once IBKR Mobile Authentication (IB Key) has been activated on your mobile device, it will authenticate your login from both IBKR apps…

Please make sure that the entire operation of entering the codes in the activation screen does not exceed the code validity time window (30 seconds). Also, you should not use a code which is already about to expire but wait for a fresh one. If the code is nevertheless rejected, please check that your device internal clock is correct and automatically synced with the current time…

Once your security device is activated, each time you log in to Client Portal, TWS or IBKR Mobile you will be required to enter two authentication factors: your username/password combination and the security code generated by your device…

In general it is not possible to have multiple Mobile Authenticator apps generating valid codes at the same time for a given user. Every time you activate a user, a new QR code (and hence a new secret key) is generated and the last key will override all the previous ones. Therefore, only the last Mobile Authenticator app that you have activated, will generate valid codes for that user. The other apps will generate invalid codes, which will be rejected upon login…