Hi Sandra,
you have two options:
- Recover website from backup
- OR, use FTP and using SPPB 5.x package (com_sppagebuilder_pro_v5.3.2.zip) upload & override all files manually:
- Files & folders from folder "admin" goes here: administrator\components\com_sppagebuilder
- Files & folder from folder "site" goes here: components\com_sppagebuilder
- Files & folders from folder "plugins" goes here: plugins
Probably not all files were correctly uploaded during your first try, unfortunately this happens from time to time, even in WordPress.
As the LAST STEP, reinstall component again.