Laptop not working

I went to the store on the 23 november bought lenovo laptop, last week thursday on the 13th november , i decided to see the laptop and check it as its for my daughter , for her studies and the screen is blank and black , and its says screen repair, i sent my daughter to take it back to the store , The honourable mr Nicholas said the laptop need to be repaired, and you have to leave it in the stores for repaires, i called nicholas and i even asked my daughter to give her the phone so i can speak to him he refused, and its highly impossible for laptop to work for two weeks, i paid it for cash, now am sitting with the item which is not working, kindly help me to get my money bak , please.