UPDATE: The dining reservation system is now working once again.
Going by a message within the My Disney Experience (MDE app), the ability to make new dining reservations is currently down.
Even though Disney revealed that the MDE app and website now the preferred way for making new reservations, guests cannot do so at this time.
It would appear the entire dining reservation is down right now, as the message says that new reservations by phone are unavailable too. FastPass+ and tickets appear to be unaffected.
Stay tuned to Orlando Theme Park Zone as we continue to follow this story.
Source: Blog Mickey