low supply - any suggestions on increasing?

Kmn
I am back to work and exclusively pumping. For the last 4 weeks my supply has gone down to about an ounce/day. I started taking fenugreek - 6 a day. It's not working. I'm power pumping, drinking a ton of water, I can't get my milk back. Does anyone have this problem? How'd you fix it? Should I take more of the fenugreek?