In a post shared on their social media accounts, the University Altay fans, who also shared a photo of the banner that was not allowed into the stadium, made the following statement regarding the grievance they experienced:

"We wish our National Team success on the road to the World Cup.
Although our banner was prepared after reviewing and following the rules set by FIFA, it was not allowed into the stadium during the Australia-Turkey match on the grounds that it was a 'prohibited item.' While we do not understand what the prohibited situation is, we wanted to share this incident we experienced with the public."
News Source: 12punto