Airtel Prepaid Lifetime Sim
My Mobile is on always incoming not working from 5days message says mobile is conection erro

Dear sir / madam

i am using Airtel prepaid from one year always there is some problem come monthly. Now i did life time till Licence that is 27 September 2021 but now i am facing a problem from Five days i am calling to my number message heared the mobile is conection error i want to know how it will ge cleared my no is 9940331510