Yes -Do you have a WDW Resort reservation? Only people with resort AND ticket/AP can book parks right now
I posted this at 12pm today and haven't made much progress since then:
After 2 hours on hold with MDE technical support, I was told that the override to make park reservations by phone is no longer working. I have 11/20 and 4/21 DVC reservations and an AP (expires 12/20 and a renewal certificate that expires 12/21) but could only book three of the 5 days of my 11/20 trip. I used Chrome in incognito mode and my resort stays & APs are listed properly in MDE. I was told that they are well aware of the DVC/AP issue and are currently working on it, and maybe that's why the phone override no longer works. It might be fixed by later today.