breastfeeding after you've stopped?

Darlene • 24, Single Mommy to a beautiful baby girl born on June 14, 2016💓
My daughter just turned 3 months, and due to her being in the NICU and me not being able to make a lot of milk she drank formula. Well she's been through 3 different formulas and she's still having a hard time adjusting to her similac sensitive( which is VERY expensive) and wic doesn't give it to me...I was wondering if I could start pumping again to make my milk come back and if it's even possible? And if it is what could I do or take to help my supply come back. Any advice would be appreciated.