Buffet disaster

Booked a big table for 16 people for the buffet for 7pm. The food in the Chinese buffet was cold. After about 45min there was almost no sushi dishes on the belt going round. The 2 trays normally prepared with various sushi pieces was non existant and never refilled (Chinese as well). By 8pm there was probably 5 dishes going around on the belt. Unfortunately I had no means of taking a photo as proof. Patrons were getting up and looking for both Chinese and sushi but none appeared. As we have been going to this branch since it opened, we found this situation very strange as our group normally has the buffet and there is always plenty to go around. Due to there being no food, it did not take long for the restaurant to empty.