Reasons why cats don't sleep and run around at night:
1. Cats eat, drink, and sleep well during the day, and are full of energy at night, so they move around to burn off their energy.
2. It's possible that the cat lacks a sense of security in the new environment and is overly vigilant.
3. Cats are naturally nocturnal hunters, and they will check around at night to see if there are any intruders.
4. When a cat is in heat, it will meow incessantly day and night. If the meows are not sharp, it may be sick and in pain.
5. It's possible that there's an unfamiliar smell in the house, causing the cat to run around to release the scent and reclaim its territory.
6. If the owner does not deworm the cat for a long time, the cat will be itchy due to fleas, unable to sleep, and will run around everywhere.
7. Cats can also feel uncomfortable and run around at home, refusing to sleep, due to hypersensitivity syndrome.
8. Recently, when the owner took the cat to get vaccinations, a bath, or to have its nails trimmed, the cat was frightened and exhibited a stress response, such as not sleeping and running around. 
If your cat is running around at night and won't sleep, be careful:
1. Before going to sleep, the owner should prepare the things the cat needs.
2. If the owner is home during the day, play with the cat more to reduce the cat's daytime nap time. If no one is home, prepare more toys for it.
3. If conditions permit, you can keep several cats so that they can play and fight with each other, thus diverting their attention.
4. Owners can prepare a midnight snack for their cats. Once the cats are full, they may want to sleep instead of running around.
5. Spaying or neutering your cat will reduce the frequency of it howling and running around at night.
6. The owner can put the cat in another room or in a cage, prepare the necessary items for the cat, and let the cat play by itself.
7. Owners should pay close attention to their cat's health and take the cat to the vet promptly if any problems arise.
