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I have valid ESTA from 1.5 years ago when I stayed in Pennsylvania. I now need to travel to the US again, but this time I only need to do so for a layover en route to Canada. When I try to update the travel details on my ESTA, I can't change my answer to the question "Is your travel to the US occurring in transit to another country?" from "no" to "yes". Do I need a new ESTA, or should I just delete all of the information under "Address while in the US"?