Everytime I update the iOS on the iPhone 5S the Nano SIM card gets damaged and I cant make any outgoing calls. But I can receive call, send and receive SMS, send and receive mail. Whatsapp chat, apps download etc. Why is that??

Everytime I update the iOS on the iPhone 5S the Nano SIM card gets damaged and I cant make any outgoing calls. But I can receive call, send and receive SMS, send and receive mail. Whatsapp chat, apps download etc. Every thing works perfectly. Every thing except making calls. Why is that?? Is there a problem with the Phone#s hardware or is it a problem with the Nano SIM Card? I have so far changed 3 SIM cards and everytime and it takes 24-32 hrs to activate the SIM and not to mention the pain of applying and getting a new Nano SIM card.

My mobile carriers is Airtel (India) aka Bharti Airtel (India)

If someone can suggest what I should do to rectify this problem I would be really grateful

Regards

Mark