Error message on mutation: API-change_column_value

Hello team,
I’m new to GraphQL and monday.com, though I’m trying to figure this query out. Wonder if there’s something I’m doing wrong in my javascript. If this is something simple, please advise:

const putInvoiceNumber = `
  mutation insertInvoiceJSON($board_id: Int!, $item_id: Int!, $columnValues: JSON!) {
    change_column_value(
      board_id:$board_id,
      item_id:$item_id,
      column_id:"text9",
      value: $columnValues)
    {
        id
    }
  }
`

let putInvoiceNumber_data = await queryFetcher(putInvoiceNumber,
      {     "board_id": board_id,
            "item_id": item_id,
            "column_id": "text9",
            "columnValues": {"text":"STA1004"}
       }, mondayToken)
console.log(putInvoiceNumber_data)


function queryFetcher(query, variables, key=bearerKey) {
    return fetch(api_uri, {
        method: 'POST',
        headers: {
            'Authorization': key,
            'Content-Type': 'application/json',
        },
        body: JSON.stringify({
            query: query,
            variables: variables
        })
    })
    .then(res => res.json())
}


And here's the output of the console.log:

{
  errors: [
    {
      extensions: [Object],
      message: 'Cannot query field "change_column_value" on type "Mutation".',
      locations: [Array]
    }
  ]
}

Any help is greatly appreciated. All the IDs, tokens, and column_names are correct (because they work in the prior similar calls. Only failing to change this value.

One small edit,
From the APIplayground I can change the Status column:

mutation insertInvoiceData($board_id: Int!, $item_id: Int!, $column_id: String!, $value: JSON!)
{
  change_column_value(
    board_id:$board_id,
    item_id:$item_id,
    column_id:$column_id,
    value: $value)
  {
   		id
  }
}

with the value passed as this object:

{"board_id": 4894533225,
  "item_id": 5095877905,
  "column_id":"status",
  "value":"{\\"label\\": \\"Exception\\"}"
}

but changing the value object to the following is not working:

{"board_id": 4894533225,
  "item_id": 5095877905,
  "column_id":"text9",
  "value":"{\\"text\\": \\"STA1005\\"}"
}

Error message:
"error_message": "invalid value, please check our API documentation for the correct data structure for this column. https://developer.monday.com/api-reference/docs/change-column-values",