At some point, you must have gone to the Web Vault’s Settings page and enabled Two-Step Login using an Authenticator; setting this up is a multi-step process, which is highly unlikely to have been completed accidentally.
It seems likely that this is, in fact, an authenticator key for her Bitwarden account, and it should work unless one of you later disabled and re-enabled Two-Step Login with Authenticator for the Bitwarden account.
If what you have is the correct key, then the most likely reason that you are having trouble using the authenticator codes is that the system clock on your devices is not accurate (running fast or running slow, or set to the wrong time zone). Please go to time.gov, and compare the time shown by Android phone to the official time. Do the same for the laptop computer.
Yes. If the error message (“Invalid verification code”) persists after you fix the clocks on the Android phone and on the laptop, then you must have stored the Bitwarden authenticator key in a different authenticator app. This would not necessarily need to be the Bitwarden Authenticator app — there are many others (e.g., Google, Microsoft, Authy, Ente, 2FAS, Aegis, Raivo, etc.). Some of these authenticators also have desktop apps (or browser extensions), so you should check all of your phones and computers to see if there are any authenticator apps installed that may contain the relevant Bitwarden key.
Yes, you need to obtain a copy of the key when you first enable Two-Step Login for your Bitwarden account, and store it is a safe place.
If you’re both logging into the same (shared) account, then please note that this is not permitted by Bitwarden’s Terms of Service. If you meant something else, please clarify.
Are you already logged in to the Bitwarden account? If the two of you are in fact using the same Bitwarden account, then there may be a chance for you to use your own logged-in app or extension to access the Web Vault. This will only work if you can find a web browser that you have previously used to log in to the Web Vault (and where the browser data have not been cleared since you previously logged in). To attempt this approach, go to the Web Vault login page, enter your Bitwarden email address, and click Continue; on the next screen, check if there is a button labeled Log in with device, just below the button that says Log in with master password. If you see the Log in with device button, then make sure that your other Bitwarden app or extension (where you are already logged in ) is unlocked, and then press the Log in with device button on the Web Vault login form. You should then see a prompt on your other app, asking you to authorize the login.
By logging in to the Web Vault, you will be able to obtain the Two-Step Login Recovery code, and reconfigure your authenticator key (by deleting the current key, and setting up a new one).