[Yandex Cloud documentation](../../../index.md) > [Yandex DataLens](../../index.md) > Troubleshooting > Unknown dimension for window

# [Yandex DataLens] Unknown dimension for window

`ERR.DS_API.FORMULA.UNKNOWN_WINDOW_DIMENSION`

This error occurs when a dimension not involved in the chart building (i.e., it cannot be found in any of its sections) is used in the window function with the [AMONG](../../concepts/window-function-tutorial.md#among) grouping.

To fix the error, drag the indicated dimension into one of the chart sections or use a different dimension.