Hi. I Have 3& Half Month Old Son. He Had

Hi. I have 3& half month old son. He had brancho pnemonia a month before. He was at NICU for a week During that time they said i couldn't breastfeed him directly due to heavy cough. But when he is recovered my lactation reduced a lot. Till now no improvement from my side. Though im nursing him to get better. What should i do sir or ma'am? Stop trying? and he is on nan pro 1 now.is it safe to use nestle?