The ledger setup could not be read: the ledger is not set up, or the connected schema is not the intended one. 422.
OPDC API error code
LEDGER_SETUP_MISSING
HTTP status 422
The API answers with a problem document (RFC 9457) whose type is https://twinn.engineering/errors/ledger-setup-missing, and with X-Error-Code: LEDGER_SETUP_MISSING. Branch on the code, never on the detail text.