Buy and Build Hardware in Bethlehem Shamelessly Ripped Me Off

I bought 30 boxes of ceramic tiles from Buy and Build Hardware in Bethlehem in Dec 2023. The invoice I received clearly shows that I paid for 30 boxes with each box having 8 tiles. Buy and Build Hardware delivered 30 boxes, but with each box having 5 tiles instead of 8 tiles that paid for as reflected in my invoice. Buy and Build Hardware originally blamed their supplier and refused to refund me nor deliver the balance of the tiles. At the end, they agreed to deliver the balance of the tiles (3 tiles for each of the 30 boxes that I paid for). It's now 14 months later and they haven't delivered the tiles as promised despite me making several requests and reminders. The owner of Buy and Build Hardware is now not even taking my calls. Can someone help me with info on how I can resolve this issue??