The UPC or EAN code is a standardized code that is used to identify products (think of it as a barcode on a product you buy at a supermarket). Since your release is now a product, it needs to have a UPC or EAN code.
If you have released your album/EP/single before, it will have a code already, and you should use the same code. Please make sure to specify the original release date and the barcode in the fields provided.
If your release is already on music services and you’re switching distributors, using the same barcode when you release through SoundCloud will ensure that the playcounts and playlist placements on your previous release will be kept.
And don’t worry, if you don’t have a barcode yet, we’ll create one for you.