2 months old weight gain fo

My Baby is 2 months old (conceived on 30th June ) he was 3 kg during childbirth ... According to development diagram, he should be 5kg now bt his weight is just 4.5 kg doc is concerned abt this.. he bolsters rearward every 2-3 hrs for approx 45 mins ... At night he needs to encourage each 1 hour so once in a day we go him equation nourish. At that point just he'll rest ... Is there whatever else should be given for weight pick up ... Like janam ghunti, or some ayurvedic supplement and so forth. Please help me.