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I am from Australia and planning to visit Canada and U.S this year. I got my ESTA approval but not sure about coming to U.S. twice in a month. I will be visiting NY from Toronto and then back to Toronto and then Vancouver. From there I am planning a trip to LV & LA. Will there be an issue as my second visit will be in a couple of weeks time again to U.S. Any help please as I am not sure about this, thanks.