Bought Inverter at Brights Hardware Watergate

I have purchased anInverter at Brights Hardware Watergate in January 2023. Returned the Inverter on the 31st May due to it being faulty .I was advised it will take about 2 weeks to have it tested and see what is wrong .No one would call from the store we have to call the Technical department all the time to follow up what is going on.We were advised the motherboard was faulty and they looking for a part to fix it .So to my knowledge if it is the motherboard it was a factory fault ,however not willing to give new one we need to wait every time get told we just need to wait which as a Customer is not a valid reason .So if the manufacturer does not have a turn around time for repairs how does the help the consumer.Why not replace the product and take the faulty product up with supplier.We have bought the product to make life a bit easier however we paid for something we not sitting with .Its been a month now already and still no inverter.The i just no urgency in having the matter resolved .The product is also still under warranty .