Ink cartraiges will not read on Epson 7800

I have bought carts and ink for my 7800 with the intention of switching as my Epson carts run out. I have never been able to get the printer to recognize the bulk carts. I have bought a new set of chips but still doesn’t work. I have tried everything I have read on the forums without success. I have had to buy new Epson carts 3 times now. Please advise