Vanguard Ichigo quest line is broken

[humble meadow]

When I try to sacrifice evolved aizen to the mask for the quest line it doesn’t work anyone know what I can do to fix it?

[signal tree]

unlock aizen

[humble meadow]

how do I do that?

[signal tree]

go to your unit inventory and select aizen, at the top there is a lock icon

press that to unlock him

[humble meadow]

tysm

[signal tree]