Clogged ducts won’t unclog! Help!

The right side of my breast has been so engorged over the past 2 days... I have been trying to feed/pump on that side to relieve it at least every 2-3 hours, but there are still these hardened areas that won’t relieve. It gets all red and painful on the outside... I got antibiotics from my OB for mastitis to see if that helps. I am only on day 2 of that. I know that the clogged ducts are the cause, I just don’t know how to fix the root problem. 😞 I’ve tried warm compresses before feeding as well. Nothing seems to help! Any advice??