If you have Traktor Pro 3 already, then presumably that appears in Native Access?
I wouldn't expect it to be listed twice, if it's the same software.
This just means you can sell your old gear, or old traktor license and still have one from the s3.
I'm not sure what you are expecting.
if you want to make sure, you should see your s3 on this page https://www.native-instruments.com/en/my-account/my-products-serials-downloads/