DUPLICATE_HEADER
File {0} repeats column {1}: there is no way to tell which of the two counts. Leave it just once
Category: Customers
Example response
When this error occurs, the API returns a JSON response with the following shape:
{
"type": "https://docs.beel.es/errors/DUPLICATE_HEADER",
"title": "DUPLICATE_HEADER",
"detail": "File {0} repeats column {1}: there is no way to tell which of the two counts. Leave it just once",
"instance": "/v1/<resource>",
"errors": [],
"success": false,
"error": {
"code": "DUPLICATE_HEADER",
"message": "File {0} repeats column {1}: there is no way to tell which of the two counts. Leave it just once",
"details": {}
},
"meta": {
"timestamp": "2026-05-21T10:00:00Z",
"request_id": "4bf92f3577b34da6a3ce929d0e0e4736"
}
}The type URI is stable and always resolves to this page.
Message
Send the request with Accept-Language: <es|en|ca> to receive the message in your preferred language.
Tokens like
{0}are runtime arguments — the backend fills them with actual values before responding.
Other errors in this category
ALTERNATIVE_ID_AND_NIF_EXCLUSIVE
The customer cannot carry both a NIF and an alternative identifier. Use only one
ALTERNATIVE_ID_INVALID
The alternative identifier is not valid
ALTERNATIVE_ID_REQUIRES_SPAIN
Type NOT_REGISTERED (07) is only valid for Spain; received country: ''{0}''
ALTERNATIVE_ID_SPAIN_INVALID_TYPE
For customers with country ES only types PASSPORT (03) or NOT_REGISTERED (07) are allowed
BULK_VALIDATION_ERROR
One or more customers in the batch are invalid; none were created