Most services that use standard TOTP codes have backup codes that you can print out and store in a safe, and the ones that don't you can save the QR code that e

Most services that use standard TOTP codes have backup codes that you can print out and store in a safe, and the ones that don't you can save the QR code that enrolls the 2FA app and use it again to re-enroll a new device if needed. Obviously the backup codes are preferred as you're not storing a master key to all future codes, but it's a lot easier to manage than a second device (at least for me).