> ## Documentation Index > Fetch the complete documentation index at: https://docs.codaclean.io/llms.txt > Use this file to discover all available pages before exploring further. # Errors > Error format, HTTP status codes and error codes returned by the Codaclean API. ## Error format Errors are returned as JSON with a `message`: | Field | Description | | ------------ | -------------------------------------------------------------------- | | `message` | Human-readable description. Do not parse it: it can change. | | `code` | Stable, machine-readable error code. Base your error handling on it. | | `fields` | Offending fields, with `unknownField` and `fieldNotUpdatable`. | | `candidates` | Connectors to choose from, with `connectorSelectionRequired`. | `code` is returned by the customers, mandates and reference-data endpoints. The file and upload endpoints return a `message` only. The token endpoint also returns an `error` field on its `500` response. ## HTTP status codes | Status | Meaning | | ------ | ------------------------------------------------------------------------------------------------- | | `400` | The request is invalid. Fix it before retrying. | | `401` | The ID token is missing, invalid or expired, or the user cannot use the API. Refresh the token. | | `403` | The API key is missing or invalid, a scope is missing, or the user has no access to the resource. | | `404` | The resource does not exist or is not visible to the user. | | `409` | Conflict with the current state (already exists, already archived, already acknowledged…). | | `422` | The request is valid but cannot be processed as is. See the error code. | | `429` | Rate limit or quota exceeded. | | `500` | Unexpected error. Retry later. | | `502` | Upload credentials could not be issued. Retry later. | **See also:** [Rate limits](/api/rate-limits) ## Error codes | Code | Status | Meaning | | ------------------------------ | ------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `invalidPayload` | 400 | The body is not a JSON object, or a required field is missing or invalid. | | `unknownField` | 400 | The body contains fields the endpoint does not accept. See `fields`. | | `fieldNotUpdatable` | 400 | The field cannot be changed with `PATCH /customers/{customerId}`. See `fields`. | | `invalidIdentifier` | 400 | The customer or mandate identifier is malformed. | | `invalidEnterpriseNumber` | 400 | The enterprise number is not valid. | | `invalidIban` | 400 | The IBAN is not valid. | | `forbiddenScope` | 403 | Your API key lacks the scope the endpoint requires. | | `accessDenied` | 403 | The customer exists but is outside the user's access. | | `belongsToAnotherTenant` | 403 | The enterprise number or IBAN is already registered by another accounting firm. To move a customer between firms, the accountant must contact Codaclean support to start a transfer procedure, which requires the end customer's agreement. | | `customerNotFound` | 404 | The customer does not exist or belongs to another accounting firm. | | `ibanNotFound` | 404 | The IBAN is not linked to this customer. | | `payrollProviderNotFound` | 404 | Unknown payroll provider code, or not linked to this customer. | | `mandateNotFound` | 404 | The mandate does not exist or is not visible to the user. | | `bankNotSupported` | 404 | Codaclean cannot request a mandate for this bank. | | `customerAlreadyExists` | 409 | A customer with this enterprise number already exists in the accounting firm. | | `customerAlreadyArchived` | 409 | The customer has been archived. | | `ibanAlreadyInUse` | 409 | The IBAN is already linked to a customer of the accounting firm. | | `payrollProviderAlreadyLinked` | 409 | The payroll provider is already linked to this customer. | | `mandateAlreadyRequested` | 409 | A mandate request already exists for this customer and bank account or payroll provider. | | `connectorSelectionRequired` | 422 | Several connectors match the bank. Call again with one of the `candidates`' `connectorId`. | | `connectorUnavailable` | 422 | No usable connector for this bank, or the `connectorId` sent is unknown. | **See also:** [Scopes](/api/scopes) · [Data access](/api/data-access) ## Customers of another accounting firm The API never reveals another accounting firm's data. Two cases can occur: * **You read or change a customer by its identifier** and it belongs to another firm: `404 customerNotFound`, exactly as if it did not exist. * **You create a customer or add an IBAN** that another firm already registered: `403 belongsToAnotherTenant`. The call cannot succeed, so the API tells you why, without naming the other firm. ## Upload errors The upload endpoints return these values in `message`: | Message | Status | Meaning | | ------------------------ | ------ | -------------------------------------------------------------------- | | `upload_not_allowed` | 403 | Uploading is not enabled for the accounting firm. Contact Codaclean. | | `sts_assume_role_failed` | 502 | The credentials could not be issued. Retry later. |