Airtel
My new sim has stopped

Sir,

i have purchased new airtel sim about 3 or 4 weeks ago... from purchased date after 1 week its stopped. when i goes to dealer he said that airtel customer care has call you but u have not attend it... but i havnot got any call... and now its sim registeraion is failed... what i can do... on that sim i have about 200 to 250 rupees its number is 8968857002... i hope u will help me