Pumping nothing

Am

So I’ve never really gotten anything with the pump especially out if my left breastfeeding. Even when engorged. My sons pedi said that my body knows the difference and wants to hold it for my son. I have absolutely no issues feeding him from either breast. He’s 10 months and I’ve just gotten a hospital grade pump from wic and I still get absolutely nothing. I’m due with another in November will be having my c-section that last week of October and I’d really like to be able to pump. My son is still breastfeeding a lot! I have no problem bf two kids but I’d like some freedom my Master uses my bf as an excuse to not be alone with our son for more than 30 minutes. Any recommendations on how I can make my body release the milk. I’d really like the willow pump but don’t want to spend that kind of money on a pump that I won’t get results with. I know I’m using the right size flanges I try for 30 minutes or longer. But don’t have any success even with engorged breast’s. Any advice, Rios, encouragement will be greatly appreciated