You will need to restore your wallet every time you log in from a different browser, clear your cache, or log in from a private tab. In order to do that, you need your backup file and the corresponding password.
Go to https://guarda.co/app and select Import or Restore, then Restore from Backup. Either drag and drop the .txt file with your backup into the specified field, find it in your files via Browse, or enter the code manually. Then enter your password. Welcome back to Guarda!