iPhone drip

I bought my very first iPhone and I must say I am very disappointed. After guarantee of my iPhone that where things went south. Firstly it was the battery of my iPhone, I went back to them to get it fixed mind you they charge me. After fixing it the back camera and a touch of my iPhone went black, me again I went to them to get it fixed. I waited there the guy which was fixing my phone told me that nothing is damaged just *****s but again a week later the camera went black again, I told them and I had to pay again , they gave me no receipt no nothing and still my back camera is not working till now. The problem of them all my iPhone now does not read SIM card , always stating the is no services, even if I take out the SIM card tray it’s does not read that “the is no SIM card”. I’m highly disappointed