DVD's not replaced when defective

I really like takealot and use them often. I've never had any issues with returns. Recently I received a defective DVD (stops playing a few minutes from the end of the movie - most dramatic of all scenes!!), and takealot won't replace it claiming that: a) it is against company policy (changes made in 2018); and b) it may have been my DVD player that damaged the DVD???

a) what does a 6 month limited warranty mean if a defective DVD is not replaced by it? b) we have a rather large collection of DVD's - none of them have this issue.

I'm really disappointed. If I tried to return the product and get a refund, I would totally understand but I requested that the defective DVD be replaced with a new one - same movie!