From the point of view of an external observer, matter falling into the black hole is supposed to never cross the event horizon due to time dilation.
At the same time, black holes are supposed to constantly grow in size by consuming further matter.
How do you reconcile these viewpoints? How can a black hole grow in a finite time (from the POV of an external observer) if nothing can can cross its event horizon in a finite time from the point of view of the very same observer?