Idutywa fashion world won't refund me

I bought a nursing top for my mom from Idutywa fashion world on the 30th of Dec 2019. When I got home , it didn't fit. So o took it back on the 31st of Dec but there was not other sizes then I asked for a refund as it is my right. I was told they dont do refunds during December holidays. Can someone explain what the that means?