We can't work on reproducing the issue and fixing the issue because we don't have enough information about it, could you please reply to my questions?
- Did you install Drupal using our installers, virtual machines or cloud images? In case you used the native installers, could you please let us know which Operating System you use?
- Could you please share with us the links to the tutorials that you followed to create your website and to try to change it back?
- Have you performed any other change in the configuration after deploying Bitnami Drupal stack?
Note that there is a lot of Drush tutorials like this one where you can find more information about it
This FAQ section will be useful for you when running commands in the stack