Refund

I purchased ink cartridges from this store , both black and colour .....took it for a first refill after a while....ink cartridge refuse to print giving error codes...I did the necessary troubleshooting but it did not work. I then took it back to the inky shop seadoone mall and was told colour cartridge add a default and it would not print....was told I would get refund .....went back after a week no refund.....where is my refund?