Poor Customer care

I bought a Brother LC529XLBK black ink on 27 July 2015 and inserted in my Brother printer and the Cannot detect ink was suddenly displayed. I have gone to the Store and I feel that I was given a defective ink cartridge. I thought that another ink cartridge would be inserted to test, but was told that I can't be assisted. I feel as a customer a loser and was not given proper customer care and wasted my time and effort on coming to the store. I expected to be given another product or the problem being solved. We bought the Brother MFC J200 late last year.<br> <br> We are an SMME and are not able to function for 2 days and it has cost us dearly.