When you add accounts to your authenticator app, you can just print out the QR code (take screenshot). Then you have a physical offline backup of the TOTP secr

When you add accounts to your authenticator app, you can just print out the QR code (take screenshot). Then you have a physical offline backup of the TOTP secret in a QR code with error correction. Store those sheets of paper in a folder somewhere safe. Also consider using a yubikey for TOTP -- but do a paper backup regardless.