> ## Documentation Index > Fetch the complete documentation index at: https://docs.connectly.ai/llms.txt > Use this file to discover all available pages before exploring further. # Error Codes > Reference for all Connectly API error types and error codes — structure, causes, and how to handle them ❌ When a Connectly API call fails, the response body contains a structured JSON object that tells you exactly what went wrong. ## Error response structure ```json theme={null} { "message": "Failed to send a message because more than 24 hours have passed since the customer last replied", "type": "ERROR_TYPE_DEADLINE_EXCEEDED", "code": "ERROR_CODE_MESSAGE_OUTSIDE_OF_ELIGIBILITY_WINDOW", "userTitle": "Failed to send a message because more than 24 hours have passed since the customer last replied", "userMessage": "Pass along the connectly trace id 'cnct_trace_id' to the team for more information.", "cntTraceId": "11824978358485860716", "details": {} } ``` | Field | Description | | ------------- | ----------------------------------------------------------------------------------------------------------------------------- | | `message` | Human-readable description of the error. | | `type` | Broad error category. See [Error types](#error-types) below. | | `code` | Specific error code identifying the exact failure. See [Error codes](#error-codes) below. | | `userTitle` | Expanded error description suitable for display. | | `userMessage` | Troubleshooting instructions. | | `cntTraceId` | Connectly trace ID. Include this when filing a support request — it lets Connectly engineers locate the exact failed request. | | `details` | Additional structured detail, when available. | *** ## Error codes | Code | Cause | | -------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `ERROR_CODE_INVALID_SENDER_ID` | The phone number used as the sender is not valid. | | `ERROR_CODE_PHONE_NUMBER_BAD_FORMAT` | The recipient phone number is in an incorrect format. | | `ERROR_CODE_MESSAGE_ATTACHMENTS_NUMBER_INVALID` | Invalid number of attachments. Connectly supports only one attachment per message. | | `ERROR_CODE_MESSAGE_TEXT_EMPTY` | The message `text` field is empty. | | `ERROR_CODE_MESSAGE_TEMPLATE_NOT_FOUND` | No template found matching the specified name and language. Create and approve the template first. | | `ERROR_CODE_MESSAGE_TEMPLATE_INPUT_INVALID` | The template inputs provided are not valid. | | `ERROR_CODE_MESSAGE_ATTACHMENT_EMPTY` | The attachment URL field is empty. | | `ERROR_CODE_MESSAGE_ATTACHMENT_INVALID` | The attachment URL is invalid and cannot be parsed. | | `ERROR_CODE_BUSINESS_MISSES_MATCHING_CHANNEL` | The business account is missing a sender channel of the required channel type. | | `ERROR_CODE_MESSAGE_OUTSIDE_OF_ELIGIBILITY_WINDOW` | More than 24 hours have passed since the customer last messaged you. Use the [template message API](/message-api/send-template-message) instead. | | `ERROR_CODE_BUSINESS_REACHED_LIMITS` | The business has reached messaging restrictions on this channel — too many previous messages were blocked or flagged as spam. | | `ERROR_CODE_MESSAGE_SELF_INVALID` | This message type cannot be sent to yourself. Use a different recipient. | | `ERROR_CODE_MESSAGE_PHONE_NUMBER_INVALID` | The recipient phone number is invalid. | | `ERROR_CODE_MESSAGE_CUSTOMER_OPTED_OUT` | The customer has opted out of receiving template messages. | | `ERROR_CODE_MESSAGE_CUSTOMER_NO_CONVERSATION_INITIATION` | You cannot use the session message API when the customer has not sent the first message. Use the [template message API](/message-api/send-template-message) to reach out first. | | `ERROR_CODE_BUSINESS_KEY_SECRET_ABSENT` | The business API secret has not been initialized. Contact the Connectly team. | | `ERROR_CODE_MESSAGE_TEMPLATE_DELETED` | New language content cannot be added while existing language content is being deleted. Try again in 4 weeks, or create a new template. | | `ERROR_CODE_MESSAGE_TEMPLATE_INVALID_PARAM` | An invalid template parameter was provided. Check that all variables, buttons, and parameters are present and correct. | | `ERROR_CODE_BUSINESS_RATE_LIMIT_REACHED` | The business has exceeded the API rate limit. | *** ## Error types Error types represent broad categories. Use `type` to determine the right corrective action before inspecting the specific `code`. | Type | Meaning | | ------------------------------ | ------------------------------------------------------------------------------------------------------- | | `ERROR_TYPE_UNSPECIFIED` | Unexpected error. Contact the Connectly team with your `cntTraceId`. | | `ERROR_TYPE_AUTHENTICATION` | Invalid authentication credentials — missing or invalid API key. | | `ERROR_TYPE_AUTHORIZATION` | No authorization for the resource — e.g. the API key doesn't have access to the specified `businessId`. | | `ERROR_TYPE_RATE_LIMIT` | API rate limit exceeded. Wait before retrying. | | `ERROR_TYPE_INVALID_REQUEST` | Request payload is not valid. Refer to the API docs and fix the request body. | | `ERROR_TYPE_DEADLINE_EXCEEDED` | Request timed out. Contact the Connectly team with your `cntTraceId`. | | `ERROR_TYPE_NOT_FOUND` | The requested resource does not exist. | | `ERROR_TYPE_CONFLICT` | The resource already exists — use an update operation instead of create. | | `ERROR_TYPE_CONTEXT_CANCLED` | The client cancelled the request. Check your HTTP client timeout settings and increase the limit. | | `ERROR_TYPE_BUSINESS_LIMIT` | The business has reached its account-level limits. |