Builders Warehouse - Unsatisfactory service from builders warehouse cape gate ct

To whom it may concern:
My children bought me a Bosch GSB 18V cordless drill on the 17/06/2023 for fathers day at Builders Warehouse Cape Gate. A couple of months later I wanted to use it, in and around the house - I establish the hammer drill function on the drill is not working as it should. I took it to Builders WH Cape Gate for repairs on the 24/09/2023. The 18/10/2023 I received the unit back, with still the same issue. I went back on the 22/10/2023 to confirm the unit is still the same - they said they will send it in again for assessment. They contacted me on the 27/10/2023 for collection, on collection they said the unit was replaced. However the unit is still malfunctioning. I can and will not accept a product that is not performing as it should - you are paying a price for a product with the expectation that it will do a specific function. It's clear that the unit is not performing as it should, and thus I want a refund.