> For the complete documentation index, see [llms.txt](https://developers.felt.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.felt.com/felt-style-language/errors.md).

# Errors

Style validation errors surface as a banner in the in-app style editor, and as `422` responses with the message in the error `detail` when styling [via the REST API](/rest-api/errors-and-rate-limits.md). The JS SDK rejects the `setLayerStyle` promise with the validation message.

### Unexpected value or type

**Problem**: One of the values set in the style has an unsupported value or an invalid type.

**Solution**: Change the value to be valid.

**Error messages:**

* Attribute `'displayName'` on a legend item of type simple must be a string.
* Attribute `attribute_name` is not a number.
* Attribute `attribute_name` is not a string.
* Attribute `'lineCap'` is not a supported value. Supported values are butt, round, square.
* Attribute `'lineJoin'` is not a supported value. Supported values are bevel, round, miter.
* Visualization dashArray has to be an array with even length.
* Attribute '`offset'` must be either an array of numbers or a number.
* Attribute `'placement'` contains a not supported value. Supported values are `N`, `NE`, `E`, `SE`, `S`, `SW`, `W`, `NW`, `Center`.
* Attribute `'placement'` contains a not supported value. Supported values are `Above`, `Center`, `Below`.
* All values in `'labelAttribute'` must be a string.
* Visualization `'type'` definition must be one of `simple`, `categorical`, `numeric`, `heatmap`, `hillshade`, `h3`.
* Attribute `'showOther'` must be one of `above`, `below`. (Despite the wording, this message refers to the `otherOrder` field — `showOther` itself is a boolean, while `otherOrder` must be `"above"` or `"below"`.)

### Categorical visualization not working

**Problem**: The style defines a categorical visualization, but the maps are not showing the layer

**Error messages:**

* Categories required. A `categories` array must be defined in the *config* block when defining a categorical visualization. Read more about categorical visualizations [here](/felt-style-language/types-of-visualizations/categorical-visualizations.md).
* Not enough or too many `attribute_name` values. When defining a categorical visualization, all style and label properties must be an array with either a single value that will apply to all categories or an array with as many values as categories defined in the config block. Read more about categorical visualizations [here](/felt-style-language/types-of-visualizations/categorical-visualizations.md).


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