Poor service

I bought iPhone 11 at Edgars Greenacres,the lady that was helping me told me she can't help me with settings because battery was flat,when I got home I noticed that camera wasn't working,I returned the phone,they sent it for assessment,a week later I was called to fetch the phone.after 2 days camera went blank again I returned the phone and asked for refund they refused to refund me.i am so disappointed with their service,I haven't even used the phone,it's not even a week I bought the phone but it's giving me problems already.