How can I close the Call Center window? October 23, 2015 21:31 Updated Follow To close the Call Center window, tap on the 'X' button at the top right corner of the Call Center window. This will remove it from your smart phone's screen until another missed call occurs. Related FAQs: What is Post Call Center? How do I disable Post Call Center? Related articles How do I disable Post Call Center? What is Post Call Center? Decline Robocalls Why do certain numbers not display a name when I attempt a Number Lookup? How do I cancel my name iD subscription?