Airtel — airtel sim deactivation issue

Airtel has deactivated my sim 4 days back without any intimation. If enquired in airtel office they give reason such as phone is charged more.. So due to heat of charging (Silly reason) or phone is currupt (If currupt my other data also should be currupt) or software update (I have not permitted).
It's just a reason to charge 25 rs. (If guenine, no issue in paying 25 rs.)
Provide to activate sim in airtel app itself.. To avoid going to office... Where service providers are not costumer friendly..