New p900 Maintenance tank already?

[Oasternak]

Hi - First post here. New SC P900 is only a couple of months old. And I got a maintenance box is full warning after an exceptionally long startup today. Really? I haven’t quite finished using up the demo ink yet and the maintenance box is, in fact, full. I read that I should expect to go a year or more without changing the box. So I must be doing something dumb here. Why do you suppose my printer filled the maintenance box so quickly? Thanks!