Poooor Service still no fan

Hi I bought a Maverick computer case from Matrix in Constantia Kloof in December 2019. On completing the computer build I saw one of the fans that was included with the sale was not working. I took the faulty fan back in January 2020 and the fan was booked in. I received a call that they can replace the fan but I must bring in the Pc Case and the will replace it with a new pc case. This is ridicules as this pc is in operation already. Must the whole thing be stripped so that the case can be swapped out.