Trying to unassign a conversation

I’m trying to unassign a conversation through the intercom API.

I’m sending the following body -
“message_type”: “assignment”,
“admin_id”: “123456",
“type”: “admin”,
“assignee_id”: “0”

to the enpoint /convesations/{id}/parts.

I’m getting “Assignee not found”, even though 0 should be sent when unassigning (
When I’m sending a true valid assignee_id, it works.

What am I doing wrong?

Apparently there was a bug in this area. Intercom fixed it and now it works. Thanks!