Breastmilk supply decreasing???

Perla

So we just came back from the 6mo check up. My lo gained only 0.300kg instead of 0.600 this month. Doctor said my breastmilk supply is decreasing and told me to give her formula at night. We also started solids 10 days ago (she tries everything but she eats very little so far).

These last few weeks have been really tough and im a bit stressed.

What is your experience, could it be true?

Do you think i have chances to get back to my normal supply?