The Guna milan is 27.5 out of 36 which is above 18 that is required for marriage. Mangal dosha issue is there as Boy has strong mangal dosha while Girl is not mangalik. You should do complete horoscope matching that includes Grah milan before doing marriage. Grah milan is more powerful than Gun milan with which you should know if this is a long lasting relationship. You said that it is a second marriage. Is it for you or both.