user_has_bots

HTTP 409. The end-user still has bots, so it cannot be removed.

What to do: Stop and delete the user’s bots first (GET /v1/partner/users/{user_id}/bots, then DELETE each), then delete the user.

Every error is an RFC 9457 problem document - match on code (stable forever), show detail to humans, and quote instance when reporting an occurrence to support.