Hi, thanks for your query. After reading your description of these recurrent red bumps on the neck, by your hair line prima facie, it seems to be a condition called Acne keloidalis nuchae. In this condition mildly pruritic bumps appear around the hair on the nape of the neck which may become pus filled and later lead to chronic folliculitis. Close shaving and chronic rubbing of the area by clothing may cause this. It exclusively occurs in young men with African-American origin. You may correlate this information with your condition and i hope you find it helpful. You may consult a dermatologist for exact diagnosis and treatment.