Faulty product and worse return policy

I bought solar lights in a pack of 4 on takealot.com

It took some time to get all 4 lights installed and then we realized that one of the lights does not get any charge from the solar panel. The other 3 lights are working fine.

We logged a return and takealot came to collect the faulty light. Now takealot are refusing to process the replacement because I have to return the other three lights as well since I bought it in a pack of 4 and that is what their policy states.

Now I have to remove the working lights, wait for 4 new lights to be delivered, then install these lights (Taking up unnecessary time from me) and hope all 4 of them are working, otherwise I have to go through this whole process again.

Logically this is not making any sense. So takealot ensures that they make the return policy as painful as possible, which will ultimately result in the client getting ****ed and keep the light that does not work. It seems almost for me like a way takealot can dump all their products that is not working.