Airtel — repetitive recharge failed for airtel

Address:

East Singhbhum, Jharkhand, 831003

I have converted my airtel postpaid into airtel prepaid yesterday, today the verification done and message came the number is active after that i tried to recharge the number a 4 times (3times 249 and 1 time 199 from different payement banks and also from airtel money ) each time amt.deducted from my account but message came airtel declined the transaction . I tried to call the customer care and it said due to unsufficient balance it couldn't be connected . I tried to fill some top up but 1000 is the min. amt for topup . Please suggest what could i do to enjoy services as the way to active a number is so ridiculous, airtel must have proper guidelines to indicate some one.