Requests closure. Closing is asynchronous: a 202 Accepted returns the record with status: CLOSING, and the account reaches CLOSED once the banking partner acknowledges. Poll GET /virtual_accounts/{id} for the transition. Calling it again while a close is in flight, or after it completes, returns 200 OK. Accounts in PENDING, BLOCKED or FAILED cannot be closed and return 409 Conflict. An unknown id or an account belonging to another platform return 404 Not Found. The request body is empty.