How to make more milk

Hi momma's, I'm in desperate need of creating more milk. My son unfortunately has to go to visitation with his dad for 3 out of the 7 days. All right in a row. This started in November. Since then he will not latch anymore. This has really taken an impact on my supply and I'm not sure what to do anymore. He's 7 months old and I really don't want to have to stop breastfeeding or to supplement with formula. Does anyone have any tips? I've tried mother's milk tea, legendairy pills, I'm running out of ideas