How to make baby eat more?

My 15 weeks old son struggles with eating. Doctor told us he need Min 120 ml per kg, so should be now Min 720 ml per day... but on most days we don’t get to 700, rather close to 650-670. And there’s spot ups too. It’s been like that for a month and it’s not getting better. He gained maybe 200g in last month.

He just doesn’t seem to be interested in eating, just won’t take the bottle tit, and if we’re too forceful he will throw up. When he falls asleep feeding it’s impossible to wake him up to feed more.

I’m getting feeding anxiety everytime we’re feeding as I’m worried he will yet again be crying when we try to feed or even

Throw up again.

Any methods how to make baby eat more? He generally eats 5-6 times a day now, but the amount varies from 90 to 150 per feed.