If you are to test the SIM in the USA before your travel, please make sure to allot at least 3 hours for the entire activation process to finish. (Text or Call will not work in USA). After testing, remove the SIM card and reboot your phone once landed in your destination country. NOTE: Three UK setting messages can take up to 3 hours to come. Device needs to be kept on during the entire period. If it's more than that, please text or call us at +1 (702) 850-2781 or send us message through Amazon so we can check the status for you.