Never book an indigo airlines international flight with starting point as Bhubaneswar, odisa. The staff are not well informed and rude. Sharing my experience, I had a flight to Berlin with following itinerary Bhubaneswar to Mumbai to Abu Dhabi by indigo and then to berlin in another airlines. The Bhubaneswar indigo staff declined to issue the boarding pass demanding a visa for abu dhabi. If not more I have passed through abu dhabi at least 20-30times till now as transit. Abu Dhabi does not need a transit visa and there is on arrival visa also available for Indian nationals. All my arguments were going into deaf ears. So long story short do not book these kind of combinations as you are for sure going to have a bad day.