Airtel — airtel customer care always engaged

Address:

Kamrup, Assam

Whenever i tried to complain regarding sim card lost of airtel,the customer care always busy as urgent steps has to be taken instead.Lost simcard can be used by any other illegal person,as we know that these days can blame to anyone,thus i dont wan to occure.
Now,I have lost again post paid sim of the same that has to suddenly complain to the customer care but doing the same is such an unconditional.