Builders returns- can't return any builders item at another store.

I am very upset. I bought some lights (bolbs) at Builders warehouse a few days ago. I bought it for Helderberg / Somerset West. This is 40km away from our home. Now the issue is the builders around the corner.... Does not want me to return the bolbs to their store. They want me to drive all the way back to Somerset to return / exchange these bolbs. So this will take me nearly 2h and 80km later just to get these bolbs returned / exchanged. Also they can't tell me how long I have to return them. So for all I know if I pass by there within the next 6 months I do not know if I will be wasting my time to even get out of the car to return these bolbs. I thought Builders means return to any Builders???? I'm shocked and not supporting them again very soon.