Airtel — airtel sim ir activation

Address: 600093

Sir,
I have been using airtel prepaid sim for the past15 yrs. Recently i was deputed to japan for an assignment. I topped up my account with rs1000 and also an ir package for rs3999 validity for 30days starting from dec2nd at an airtel office in kaliamman kovil street virugambakkam. I was able to make a call from hongkong during transit to tokyo japan on the same day. Unfortunately my simstopped working after that. How do i make it work as mynumber is needed to communicate to my house, book gas etc. Pl do the needful asap. Thanks