You might need to access the product's page to check the available FAQs and PDF documents, because the Google website doesn't offer any help at all about this issue. According to some of the available calculations presented on Google, it appears that the Mephysto uses exact numbers to display the results. The error you receive indicates that the values you are trying to import are wrong. Open the file with a text editor if you have the possibility and then check the values that are shows as duplicate.