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As above picture - brought a return flight ticket from London to buenos aires and transit at JFK airport. I didn't know a transit visa is needs until I went to check in today at Gatwick airport. The travel agent didn't mention to me that I need a visa for transit with Argentina passport holder. I was so annoying and didn't know what to do for the last minute. I phoned the travel agent and he said nothing to do with him. He is just selling ticket. If I need to change the date with the same itinerary with same airline and it will cost me £768 just to change the date. My question is there any help for this critical situation?