Airtel — call drop & no network

Address:

Jalandhar, Punjab, 144002

My mob. No. Is [protected]. I am living in jalandhar city & daily go to banga city & near villages (Distt. Nawanshahr) punjab. I am facing the problem from last 2 months that most of times call drops or sometimes i receive a message from airtel that someone was calling me but my no. Was out of coverage area. My friend tried calling me sitting in front of me, full range is in my mobile handset, even then your system is saying that my mobile is switch off or out of coverage area. I am very much annoyed... Please solve this...