[Yandex Cloud documentation](../../../index.md) > [Yandex DataLens](../../index.md) > Troubleshooting > Unknown field

# [Yandex DataLens] Unknown field

`ERR.DS_API.FIELD.NOT_FOUND`

Nonexistent field used.

This error occurs whenever a chart uses a field with an identifier that is not in the dataset.
This field could have been deleted from the dataset after the chart was created.

To fix this error:

1. [Update fields](../../dataset/create-dataset.md#update-fields) in a dataset.
1. [Change](../../dataset/create-dataset.md#replace-field) or delete the fields highlighted in red.
1. Save the dataset.