> For the complete documentation index, see [llms.txt](https://ftcoders.first-tech.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ftcoders.first-tech.com/first-tech-ttp-sdk/utilities/error-codes.md).

# Error Codes

The errors listed below are returned directly through the LiveData object as the transaction progresses through various statuses, from terminal activation to approval or decline returned by the acquirer. Different `ViewData` instances will be emitted to this object, each representing a specific type of error. Some error types, such as `INTERNAL_ERROR`, may include additional subtypes. However, most errors do not have subtypes.\
\
You can find the most common errors listed below, along with immediate responses and recommended next actions to mitigate the issues encountered.

<table><thead><tr><th width="257">ViewData</th><th width="240">ErrorClass</th><th width="70">ErrorCode</th><th width="295">ProbablyReason</th><th width="352">Action1</th></tr></thead><tbody><tr><td>TerminalSessionCreatedErrorViewData</td><td>NFC_ERROR</td><td>10</td><td>Device doesn't have NFC or it is disabled</td><td>Check device specs and ask to enable NFC capability</td></tr><tr><td>TerminalSessionCreatedErrorViewData</td><td>DEVICE_STATE_FAILURE</td><td>15</td><td>App Credentials doesn't match between First Tech / MPP and Customer App (Google Play Data)</td><td>Check VersionCode, Package Name, Version Name inside App Config and Check SHA-256 generated by Google Play. One of them is not correct or registered in FT/MPP environment. Collect information and send to First Tech to analyze</td></tr><tr><td>TerminalSessionCreatedErrorViewData</td><td>INTERNAL_ERROR</td><td>18</td><td>ACTIVITY_NOT_AVAILABLE Exception. The Activity in charge to perform SDK actions stopped to working inside Android by user actions or other appications</td><td>Close and open the app (try again)</td></tr><tr><td>TerminalSessionCreatedErrorViewData</td><td>INTERNAL_ERROR</td><td>20</td><td><br>INVALID_SESSION_TIMEOUT Exception. Session time is taking longer than 180s</td><td>Check device time setting, make sure it's synced with network time and try again. TTP can't work with manual clock settings</td></tr><tr><td>TerminalSessionCreatedErrorViewData</td><td>INTERNAL_ERROR</td><td>21</td><td>ACTIVATION_WHILE_TRANSACTION_IN_FLIGHT Exception. Android Clock miss the parameters to handle the transaction</td><td>Check device time setting, make sure it's synced with network time and try again. TTP can't work with manual clock settings</td></tr><tr><td>TerminalSessionCreatedErrorViewData</td><td>INTERNAL_ERROR</td><td>1033</td><td>AUTHENTICATION_ERROR_AUTHORIZATION_GRANT_NOT_PRESENT Exception. It was caused because Scope, sdk_Client_Id or sdk_Client_Secret was invalid between First Tech and MPP </td><td>Collect information and send to First Tech to analyze</td></tr><tr><td>TerminalPaymentErrorViewData</td><td>INTERNAL_ERROR</td><td>1069</td><td><br>HTTP_NETWORK_HANDLE_TRANSACTION_RESPONSE_ERROR Exception. FT Back-End found an error while retrieving information from servers</td><td>It can be caused by an specific delay. Ask the user to try again. If it insists collect information and send to First Tech to analyze</td></tr><tr><td>TerminalPaymentErrorViewData</td><td>DISCOVERY_TIMEOUT</td><td>N/A</td><td>Card/Digital Wallet was not read in the less 30 seconds</td><td>Try again using the same card. Ask the user if they’re aware of the correct location of the NFC reading area on the device. If the error persists, try using a different card of change the device.</td></tr><tr><td>TerminalPaymentErrorViewData</td><td>MICROPHONE_USAGE_DETECTED</td><td>N/A</td><td>Terminal microphone is being used by another application during the use of the TTP app</td><td>Close all the apps and check if the current is not opened twice. Try to run the app again</td></tr></tbody></table>


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