All codes in IntentErrorCode with default messages from IntentMessages where applicable. Errors return via alertError(IntentError) on your listener.

Error code	Typical message (`IntentMessages`)
`APP_NOT_FOUND`	Payment application is not installed
`NO_INPUT_DATA_RECEIVED_VIA_INTENT`	(payment app)
`INVALID_INPUT_DATA_RECEIVED_VIA_INTENT`	(payment app)
`UN_AUTHORIZED_ACTION_TO_PAYMENT_APP`	The requested intent request is not allowed to be processed
`USER_LOGIN_CANCELLED`	User login process cancelled
`TRANSACTION_LOOKUP_CANCELLED`	Transaction lookup process cancelled
`USER_CANCEL_TRANSACTION`	The transaction has been cancelled
`NO_DATA_RECEIVED_FROM_PAYMENT_APP`	No data received from payment app
`PAYMENT_APP_CLOSED_BEFORE_RESPONSE`	Payment app closed or interrupted before returning a transaction result.
`TERMINAL_NOT_SETUP`	Payment Link / QR is not configured on this terminal.
`API_ERROR`	(varies)
`INVALID_LIMIT`	Please enter a valid integer limit
`INVALID_AMOUNT`	Please enter valid amount between 0 and 999999
`INVALID_TRANSACTION_ID`	Please provide a valid transaction uuid to perform a refund / void
`CODE_UNAUTHORIZED`	(payment app result)
`CODE_ERROR`	Invalid input params (also generic)
`CODE_RETRY`	(payment app result)
`CODE_FALLBACK`	(payment app result)
`CODE_SEE_PHONE`	(payment app result)
`CODE_DECLINED`	(payment app result)
`CODE_TIMEOUT`	(payment app result)
`CODE_CANCELLED`	Transaction cancelled (title helper)
`CODE_TERMINATED`	(payment app result)
`CODE_SERVER_ERROR`	(payment app result)
`CODE_UNSUPPORTED`	(payment app result)
`CODE_NETWORK_ERROR`	(payment app result)
`INVALID_TRANSACTION_LOOKUP_PARAM`	Invalid transaction lookup parameters provided
`INVALID_TERMINAL_DATE_TIME_ZONE`	Invalid date and time settings. User is being redirected to android settings

Additional message templates (not separate enum codes): UNSUPPORTED_PAYMENT_MODE, MULTIPLE_PAYMENT_APPS_FOUND, CODE_APP_VERSION_NOT_COMPATIBLE.

Recovery-related codes

Code	Meaning	Action
`PAYMENT_APP_CLOSED_BEFORE_RESPONSE`	Payment App closed before callback	Run transaction lookup; treat as unsuccessful unless lookup returns a passing success result
`APP_NOT_FOUND`	Payment App missing on device	Install UAT or production Payment App
`INVALID_AMOUNT`	Amount ≤ 0 or over limit	Fix amount and retry

🚧
If alertError fires on a lookup call, treat the payment as unsuccessful in your POS.

See Terminal integration flows for recovery guidance.