There could be a few different reasons why you're seeing this error:
- The user has not refreshed the page since Upscope was installed. Ask the user to refresh and try again.
- The Upscope code is not on that particular page, in which case you'll just need to add it and try again. You can check whether Upscope is installed on a page by adding ?upscopeDebug=showAlerts to the url (e.g. https://upscope.io/?upscopeDebug=showAlerts)