Why does my Ella theme collection banner image look blurry?

hi i am using Ella Shopify theme when i add banner to collections i looks blur i tried different sizes but it is still showing blur image please some one guid me to fix this issue.

Hi @MerajUddin ,
Can you kindly share your store link (with the password, if any) with us? We will check it and suggest you a solution if possible.

https://www.zemimaas.com/