Mocking Service Error for Query Parameters: Error validating parameter: expected type: JSONObject, found: String

Here is the route definition:

/products/approvedStates:

  get:

    queryParameters:

      issueStateAbbreviation:

        type: USStateAbbreviation

        required: false

    responses:

      200:

        body:

          application/json:

            type: ApprovedStatesOutput

      400:

        body:

          application/json:

            example:

              "Invalid state abbreviation."

USStateAbbreviation:

type: string

enum:

- AL

- AK

Activating the mocking service and providing one of the enum values (via dropdown) for the endpoint returns the following:

{

"code": "REQUEST_VALIDATION_ERROR",

"message": "Error validating parameter: expected type: JSONObject, found: String"

}