Since the WPBakery Page Builder plugin does not allow updating via updating the theme, so please follow these steps below to update it.
Step 1 – Go to Dashboard > Plugins. Select the WPBakery Page Builder plugin, and click Deactivate.
Step 2 – After deactivate the plugin, go to Inactive tab, select the WPBakery Page Builder plugin and click Delete. All your content such as pages, options, images and posts will not be lost or erased by doing this. However, any customizations to the plugin’s core files, such as PHP files will be lost.