I think your installation or class registry might be broken. Try doing the following things:

• See if drush rebuild works (if it does not, go to the next point).
• Go to your Drupal install directory and try to run composer install.
• If drush rebuild didn't work in the first step, try running it again now.

Please let me know if it works. Good luck!

I think your installation or class registry might be broken. Try doing the following things:

• See if drush rebuild works (if it does not, go to the next point).
• Go to your Drupal install directory and try to run composer install.
• If drush rebuild didn't work in the first step, try running it again now.