Encrypting your data and backups is one of the easiest and most important steps you can take to protect your data. In order to be able to access the encrypted data, however, you will need the password you assigned during the setup process. It is extremely important that you keep your password in a safe location that you can access when necessary, such as saving it in a password manager.
If you have lost your encryption password, it cannot be recovered. For this reason, losing this password means encrypted backups can no longer be used, potentially resulting in a loss of important data. You must then create a new backup plan and new backups of your data.