Invalid Environment Variable

import DontEditWarning from '~/components/DontEditWarning.astro'

<DontEditWarning />

:::caution[Deprecated] This error is from an older version of Astro and is no longer in use. If you are unable to upgrade your project to a more recent version, then you can consult unmaintained snapshots of older documentation for assistance. :::

EnvInvalidVariable: The following environment variable does not match the data type and/or properties defined in experimental.env.schema: KEY is not of type TYPE

What went wrong?

An environment variable does not match the data type and/or properties defined in experimental.env.schema.