Dell — dell store provide me not working battery after service

My self Anil Parmar. I have Dell Inspiration Laptop having Service Tag no. 85C0HW1. My laptop is not working since last 1 month. that's why I gone to the dell store at Shop No. 7, Saroj Plaza, 150 Ft. Rd, Near Maxus Mall, Bhayandar, 401105, . When I was submitted my laptop on dtd. 07.06.2015 that time my battery is working but when I collect my laptop on 11.06.2015 from gallery it was not working. I check my laptop infront of that Technician Mr. Sandip Gupta. He told me Charge 4 hours and after 4 hours it will work. but after 4 hours charging it was not working. only laptop started with charger. I call him Mr. Sandip Gupta he told me come back we check. but after submitting again my laptop they are help less. I told him at the time of submitting I given u working battery but after receiving you giving me not working battery, please co operate.