MrP Mobile Sells faulty cell phones.

Mr Price Mobile sold me a faulty Mint Fusion device, the device started malfunctioning 3 days after they handed it to me, I contacted them, they took the device but they brought it back still not working, they claiming there's liquid damages because apparently some green light is blinking in the motherboard and this only happens when there's liquid damages

Now they want me to continue paying them for the device, No ways MrP Mobile, you cant be selling people faulty stuff and expect payment, fix this before you start asking for funds