Ebay & Country Fried Finds Ebay Failed to uphold policy of not refunding for defective merchandise

I purchased a set of HP ink cartridges July 26,2021. On Sept 11, 2021: 11 days after the buyers protection ran out, I requested a refund from seller for defective cartridges. Seller declined to refund. I contacted ebay and was told it was 11 days out of buy protection BUT because they were defective the seller was not supposed to decline refund. Also that he would investigate my claim and see what could be done to refund my money. 

On Sept 16 I had not heard back from ebay. I got the run around. Passed to 4 different departments before I got to the last one who told me wrong info from the start. Note that I had to correct events and issues numerous times because they were not getting information entered correctly. I finally get an email saying they can't do anything because it's past the 30 days. It's still defective and I'm still out the money for cartridges I can't use. Ebay is refusing to help me resolve an issue with a deceptive seller.