91

Issuer is unavailable or unable to process

The issuer, authorization system, switch, or route is temporarily unavailable.

Outcome: Technical
Code system: UnionPay
Raw format: Two-character alphanumeric DE 39 response code

Operational context

No universal retry instruction encoded

UnionPay wording mapped to the SchemeLens “Issuer or network unavailable” concept.

Use the current scheme, provider, transaction, and advice-code rules; the raw response value alone may be insufficient for a retry decision.

Explicit mapping

SchemeLens concepts

These links are editorial mappings, not replacements for the raw source value. The relation shows how closely the wording aligns.

Normalized concepts mapped to UnionPay response code 91
Concept	Relation	Mapping note
Issuer or network unavailable	Direct semantic match	UnionPay wording mapped to the SchemeLens “Issuer or network unavailable” concept.

Namespace check

The same raw value exists elsewhere

Visa 91Issuer or switch inoperative
Mastercard 91Authorization system or issuer system inoperative
Discover 91Authorization system or issuer system inoperative
EBANX 91Issuer or switch is unavailable

Provenance

Sources used for this record

China UnionPay Open Platform: Industry and Content System Interface Specification — Appendix BOfficial, limited-scope source for two-character DE 39 values used by the documented CUPS industry and content interface.
Online specification, updated 24 August 2020; verified 27 July 2026

SchemeLens keeps source wording, normalized concepts, and operational guidance separate so later evidence can be added without rewriting the raw record.