I have recently purchased the serial number upgrade from 2 to 3. My product serial number is appearing on Native Access but when entering the serial number to register the product it comes up with an invalid message. Please help!
The OP has contacted support and it looks like there's no Traktor Pro 2 in their account, that's why the update doesn't work.
Perhaps you have it registered on your other account?
Did you download the latest release of NativeAccess?