Help to increase supply

My baby is 9 months old and I have been pumping since the day he was born, every 2-3 hours (he was a micro preemie and never perfected the latch unfortunately) but I have been going as long as 6 hours without pumping threw the night because a lady has to sleep sometimes. The last week or so my supply has dropped from 4-5oz to 1-2oz and I don’t know what to do. I power pump every morning when i wake up, and before bed, I take fenugreek 3 times a day, I drink a glass of water everytime I pump, I eat lactation cookies and drink a lactation smoothie everyday. I don’t know what else I can do, I’ve had to start supplementing with formula 1 or 2 bottles a day, I have absolutely no problem with formula, but I know that breastmilk is definitely best for him (especially since he’s a preemie with a weaker immune system) and I want to keep being able to provide that for him.

Does anyone have any other suggestions of things that I can try?

Also here’s a picture of my perfect little Superman ❤️