Airtel — pathetic customer service - unable to resolve sim problems

Address:	HX12DG
Website:	In.Airtel.Com

I have been a airtel customer for almost 10 years now and recently moved to uk. Before moving to uk i wanted to convert my airtel postpaid to prepaid as i was just using my airtel sim for bank transactions. But some airtel executive called me and changed my mind to keep the postpaid as they would provide a rs 50 postpaid plan with unlimited roaming. So i thought this would work out. But as soon as i came to uk the airtel network did not register any of the available network. So i have been calling them for past 1 month but not at all getting any help from them and i have paid the postpaid bill of rs 300 which they said it will be 50.
Now the finally as they were not able to figure out the issue, they just said that sim has problem and i have to go back to india to get a duplicate sim card. So they expect me to spend 1lakh and fly to india just for a sim card. And when i asked if a family member can take the sim card on my behalf they said that would not be possible.

My airtel number is [protected].