On 11.11.2011 I have purchased one 3G 7.2 mbps USB dungle and activated on that day 750 Rental Postpaid connection the SIM No. is 8011051447, this 750 Rental is 5 GB for 30 days as per Airtel commitment, The Airtel has committed that the speed upto 7.2 mbps and low is 300 kbps, but from that day the speed i have received below 300 kbps. On 13.13.2011 my connection showed 0 kbps and nothing opened than myself contaced with Airtel customercase no 121 one lady informed that communicate with 7070 as this is the internet customer care no after that they given 18001030405, 12134,12118 near about 04 hours myself communicate there is no one who give me the actual fact, only informed that your CREDIT LIMIT 1000 and your UNBILLED amount 1956.48 so your connection temporarily disconnected you may please be paid some amount to continue the connection. As per my plan 750 rental is surfing upto 5 GB in a month but my uses only within 300 MB which is lower than 5 GB, Today (14.11.2011) myself contacted with Airtel Executive in his number 9957599118 but no fruitful information given by him. As my plan is 750 monthly rental and 5 GB uses in a month why my connection disconnected when I have not crossed the 5 GB, if I crossed 5 GB the additional charge may be calculated. Why the credit limit given and how Rs. 1956.48 calculated as unbilled. At present what I can do?