KOBBLE_AED_4 / KOBBLE_USD_4 / KOBBLE_EUR_4 / KOBBLE_GBP_4 wallet whose partner account has been opened (typically once ACTIVE). The response body is the PDF itself (Content-Type: application/pdf, Content-Disposition: inline; filename="..."), not a JSON envelope. Read-only; no ledger impact.Confirmation letter not available for every other case — the id belongs to another client, is not a _4 product, has no partner account yet, or the partner has no letter for it (yet). Retry later when the resource is new.client/read scope. Owner-scoped.