Log into your Retailers 'myaccount' page, look for link to your 'usage data' csv file.
If it is not available to download, request it.
The file will save to your downloads folder.
Open CSV files in a text editor (like Notepad) rather than spreadsheet software if you’re unsure about the file’s contents. When you do you will see that the data is safe.
Step 2 - Data - Import, Format, Export.
Step 3 - Go Back, Upload Validated file, See Price.