They say cotinine is cleared from blood within 2 weeks - why do they say it can bedetwcted after 6 months?

Who says?: A couple of weeks is sufficient to clear cotinine. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex. Get HPV vaccine

Hair ??: “Traces of nicotine can generally be found in your hair follicles for up to three months after your last exposure. Depending on the hair test used, nicotine may be detected for up to a year after your last exposure.” REF: https://www.healthline.com/health/quit-smoking/how-long-does-nicotine-stay-in-your-system#nicotine-in-saliva-and-hair