can i get a replacement cover

bought a Hi Boost online received it yesterday , when i opened the back cover to put in the battery the cover completely cracked . i called canal walk store to find out if i can get a replacement cover , Aiden the guy at the store said it was my own fault that it broke , i was annoyed but all i want is a replacement back cover because the cover was difficult to remove which Aiden himself said he struggles with in store so how did this become my fault. i just need to find out if i can get another back cover for the Hi Boost