Hi frnds .. mera beta 4 nd half month ka hai .. wo formula milk pe hai nw his wright is 4.9kg ... uska weight nai badh raha hai kya karu pls suggest

You need to speak with his paediatrician about this. With formula fed babies the weight gain will be rapid unlike breast milk babies. So 4.9 kgs for 4.5 months is less.

doc ne bola ki its just one parameter,, it doesnt matter ,. slow weight gain is also ok

If the doc said that he is fine otherwise then don't worry. He will start gaining weight when he starts solids