[Resolved]  Nokia 2600c - 2 — does not show the network on the screen

i, Arun Kumar Srivastava of lucknow have buyed this set on the last 19th october but since i have used this set for only 4 months.after 4 months it does not show the network. i have gone to the nokia care center at6-B park road jaiswal complex hazaratganj lucknow lucknow 3 times but i got no good response. they keep my phone for at 15 days each time and return to me as it is each time. so i request you to issue the DOE so that i can replace the set.i am having all documents required