There are many reasons why dogs stay up at night and walk around grunting, for example:

1. If the dog does not consume all its energy during the day, it may feel restless and agitated at night.

Owners can appropriately increase the amount of exercise the dog gets during the day, such as taking it out for a walk or playing, which can help it sleep better at night.

2. Some dogs are very dependent on their owners. When their owners are not around, They may feel restless and anxious.

In this case, the owner can place an item with its own scent, such as old clothes or blankets, in the place where the dog sleeps to relieve the dog's uneasiness.