Kia faulty picanto within a year

My car has not been up to one year, but giving me problem. Called them and taken to the nearest Kia which is in Nahoon EL. They diagnose it one day called me to pick it up. When they gave me a report there is a part saying I must take it to the body shop. As a car brand new has not finished one year how are they making their problem mine and the guy was assisting said my car its okay bt when I drove it, it was not.... It has a strange sound when its on start like its mixing waters bt to me they say its a problm I had to fix it myself. I can't. They must take their car can't drive a faulty car and I can not fix it bcz its still under warranty. It proves that their cars are week because Im driving on a road not in a forest but within a year its faulty. Pls kindly fix this or give me a new car