Take a lot refusing to refund bad quality products

I bought an umbrella from take a lot in June along with other products and the umbrella was delivered a week late than my other products because it was lost in transit according to them. By the time the umbrella was delivered I didn't need it at the time so I didn't use it. In August when I had the need to use the Umbrella I found out it was broken when i opened it. I logged a return request and after Take a lot reviewed the umbrella they sent it back to me saying that according to their policy damaged products need to be returned with 7 days of delivery. When I check the product it has a 6 months warranty and yet they are telling me about their 7 days return policy. On their website there are complaints from other people about the same umbrella's quality and yet they are refusing to take it back.