It's normal for a cat not to poop for a day.
What should I do if my cat hasn't pooped for several days?
1. Encourage your cat to drink more water, or feed it foods with high water content, such as light vegetable porridge, meat porridge, canned food, hairball remedy, or cat treats to prevent constipation. Additionally, if your cat doesn't like to drink water, you can try a water purifier. 
2. Supplement with probiotics. This situation in cats may be due to a lack of beneficial bacteria in their bodies, leading to poor digestion. Therefore, owners can supplement with probiotics or feed them foods that promote intestinal motility, such as honey water or plain yogurt, to help with digestion.
3. Help your cat get daily exercise. This not only strengthens the bond between you and your cat, but also helps your cat digest its food.
