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# CustomerEngagementSession.Error

Errors that can occur during the engagement session.

```
enum Error
```

## Topics

### Enumeration Cases

[`case connectionFailed`](/documentation/ProximityReader/CustomerEngagementSession/Error/connectionFailed)

An error occurred while connecting to the customer.

[`case expiredCredential`](/documentation/ProximityReader/CustomerEngagementSession/Error/expiredCredential)

The credential used to create the session has expired.

[`case incompatibleRequest`](/documentation/ProximityReader/CustomerEngagementSession/Error/incompatibleRequest)

An error that indicates the request is not compatible with the connected client type or version.

[`case internalError`](/documentation/ProximityReader/CustomerEngagementSession/Error/internalError)

An error that occurs internally within the session.

[`case invalidCredential`](/documentation/ProximityReader/CustomerEngagementSession/Error/invalidCredential)

The credential used to create the session is not valid.

[`case invalidPassTypeIdentifier`](/documentation/ProximityReader/CustomerEngagementSession/Error/invalidPassTypeIdentifier)

An error that indicates the passTypeIdentifier validation failed.

[`case invalidRequest`](/documentation/ProximityReader/CustomerEngagementSession/Error/invalidRequest)

An error that indicates the request validation failed.

[`case invalidSession`](/documentation/ProximityReader/CustomerEngagementSession/Error/invalidSession)

The session is no longer active or is invalidated.

[`case notReady`](/documentation/ProximityReader/CustomerEngagementSession/Error/notReady)

The session has not yet received the `.ready` event from the customer.
The merchant must wait for the `.ready` event before sending requests.

[`case notSupported`](/documentation/ProximityReader/CustomerEngagementSession/Error/notSupported)

The current device or the environment doesn’t support this feature.

[`case pairingFailed`](/documentation/ProximityReader/CustomerEngagementSession/Error/pairingFailed)

An error occurred while pairing with the peer.

[`case paymentRequestCancelled`](/documentation/ProximityReader/CustomerEngagementSession/Error/paymentRequestCancelled)

An error indicating the payment request to the customer was cancelled.

[`case paymentRequestFailed`](/documentation/ProximityReader/CustomerEngagementSession/Error/paymentRequestFailed)

An error indicating the payment request to the customer failed.

[`case requestCancelled`](/documentation/ProximityReader/CustomerEngagementSession/Error/requestCancelled)

An error indicating the request is cancelled.

[`case requestFailed`](/documentation/ProximityReader/CustomerEngagementSession/Error/requestFailed)

An error that occurs while sending the request to the customer.

[`case sessionBusy`](/documentation/ProximityReader/CustomerEngagementSession/Error/sessionBusy)

An error indicating the session is busy due to a pending request.

[`case sessionFailed`](/documentation/ProximityReader/CustomerEngagementSession/Error/sessionFailed)

An error indicating that the framework failed to create the session.

[`case userDeclined`](/documentation/ProximityReader/CustomerEngagementSession/Error/userDeclined)

An error indicating that the customer declined to share requested information.

[`case wifiDisabled`](/documentation/ProximityReader/CustomerEngagementSession/Error/wifiDisabled)

An error indicating that Wi-Fi is turned off.

## Relationships

### Conforms To

[`Error`](/documentation/Swift/Error)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Equatable`](/documentation/Swift/Equatable)

[`Hashable`](/documentation/Swift/Hashable)

[`Sendable`](/documentation/Swift/Sendable)

---

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