Only Leaders and Co-leaders can promote and demote co-op members. If you hold one of those positions, you can change the status of lower-ranking members. Here's how:
1. Tap a member’s name in the co-op chat or in your co-op's edit window in the Co-op Building.
2. Tap the Change status button.
3. Tick the relevant status in the pop-up window.
4. A notification about the status change will appear in your co-op chat.