Ensure the temperature is suitable: Kittens need to be kept warm because they have very little body heat. You can use a hot water bottle or electric blanket to help warm them up.
Artificial feeding: If the kitten refuses to nurse, you can try feeding it goat milk powder or cat milk powder using a bottle or syringe (without the needle). Be careful to avoid milk entering its lungs.
Stimulate defecation: Gently stimulate the kitten's anus with a cotton swab to help it defecate. Sometimes kittens refuse to nurse because they cannot defecate.
Seek professional help: If the kitten continues to refuse to nurse, is in poor spirits, or has other health problems, contact a veterinarian immediately for examination and treatment.
