He and a friend, Chathura Perera, each had seven tickets for the tournament vanish.
Another fan, who gave only his first name Farhood, said his tickets had gone.
"I don’t have them anymore on the app. It might have been a hacker, I’m not sure,” he said.
FIFA acknowledged in a statement that “some spectators are currently experiencing an issue with accessing their tickets.”
“The issue is no tickets on the app," England fan John Eastern told the AP. “I’m not sure I’ll get in.”
While the fans were waiting outside, play had stopped for about seven minutes to deal with Iran goalkeeper Alireza Beiranvand's facial injury. He continued playing briefly but then was substituted.
As the kickoff approached, FIFA advised fans to check the inbox of the email account they used to register with the ticketing app.
“In case fans cannot access their email accounts, the stadium’s Ticket Resolution Point will be able to support,” FIFA said.
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