Ideally, travelers to or within the United States who have a valid tourist visa should not have their travel interrupted by immigration officials, Border Patrol agents, or employees of the Transportation Security Agency. Unfortunately, the United States government sometimes makes mistakes. When the mistakes are made by agencies within an organization as massive as the Department of Homeland Security (DHS), the mistakes can be difficult to rectify.
One resource for travelers who face border issues is the Traveler Redress Inquiry Program (TRIP). Travelers can use TRIP to alert DHS to government mistakes that delay or disrupt travel plans.