my baby boy is 4 months old .His weight is 6.4 compare with last month he is gain only 500 grams ..it is any problem or not

A. Actually 400 to 500 g is ideally considered a very healthy weight gain Sethia child and about 500 g in the last month that me Ide it age good enough so I don’t see any problem with that and that’s a good and healthy weight gain that your child is having