If NATS links go to "Spam", it means that your affiliate account has been set to "Banned".
https://tmmwiki.com/index.php/Change_Affiliate_Status
A "Banned" affiliate will not be able to login to your NATS system, and all of their traffic will be redirected to the /spam.html page on your linkdomain. Once an affiliate is banned, they are also automatically removed from the Payments Admin to prevent them from receiving payouts.
A disabled affiliate, on the other hand, will also be restricted from logging in and removed from the Payments Admin, but their traffic will still be tracked by NATS.