Broken Promises

Bought lithium batteries on 15 March 2023. Was promised a refund should batteries be incompatible. Used electrician recommended by them. Batteries weren’t fully charged and was returned for checking. It went back to their supplier twice with us waiting by 30 March I was still wyfor the batteries The electrician finally pitched up mid April and did the installation. My inverter worked for 1 day and when we had load shedding anw the inverter needed to kick in everything went dark. Unit busted. Mustek the inverter guys told us that the inverter wasn’t made for lithium batteries. Now requesting a refund Electric Wholesalers refuse wanting reports from Mustek which wasn’t forthcoming. I understand they cannot sell it as new but surely they’re not keeping their word and moved the goalposts. Could also be that they have a claim with the manufacturer as we took delivery of faulty batteries in the first place.