Hulett Packard / Takealot Returns

Having bought HP Ink Cartridges from Takealot, for many years, this last batch included a black cartridge which would not read and kept telling me to insert a cartridge. I then put in another cartridge, which works perfectly. I tried to find out about returning it to TAKEALOT (R349.00) but on going onto my order, it says it is not returnable!! Having spent the next 45 minutes with a HP customer care person, I gave up in dispair and have decided the best is to just throw this money away !!