I tried calling them and they said they cannot do waitlists anymore over the phone. Waitlists can only be done online now. But they did say that I should be able to use manage booking -> change flight to search for the award that I want to waitlist for. And that it will be smart enough to only check if I have enough points to cover the difference to waitlist. However when I searched for flights that way, no waitlist options show up for me. They said they checked on their end and that they do not see a waitlist option either. Even though I said I am able to create a new booking and be put on waitlist, they said they do not see any waitlist available on their end and that the new booking is showing old inventory. Anyways they recommended me to keep trying, use a new browser, clear cache/cookies, and if all else fails call back again tomorrow.