AOA headlined at the 'Asian Infrastructure Investment Bank' concert on Jeju Island on June 16 without ChoA.

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The girl group headlined at the 2nd annual meeting for the 'AIIB' and performed for a gathering of representatives from 77 countries. Though preparers requested all the AOA members to show up as it was an important event, ChoA, who is still taking personal time off, was not able to show.

One rep said, "The AOA members are currently here. In the end, ChoA was unable to come." Her absence is once again making fans speculate about an alternative reason for her vacation.