An unsuccessful enrollment may result from a system generated or an inputting error by the enrollee such as failure to provide complete or accurate information. A traveler who receives an “Unsuccessful Enrollment” message should contact the EVUS Call Center at 00-1-202-325-0180 or via email at email@example.com before attempting to re-enroll. The Call Center is available 24 hours per day, 7 days per week, but is closed on U.S. federal holidays. The Call Center is staffed with Mandarin speaking operators and is available to answer questions travelers might have regarding EVUS. All EVUS enrollments must be submitted online by the traveler or a third party. U.S. Embassies and Consulates are not able to provide details about EVUS enrollments or resolve the issue that caused an unsuccessful enrollment.