I'm trying to close a sales order as described here: http://mikebian.co/how-to-close-a-netsuite-salesorder-using-suitetalk/ I'm getting a weird error:

<platformCore:statusDetail type="ERROR">
            <platformCore:code>INSUFFICIENT_PERMISSION</platformCore:code>
            <platformCore:message>You do not have permissions to set a value for element item.isclosed due to one of the following reasons: 1) The field is read-only; 2) An associated feature is disabled; 3) The field is available either when a record is created or updated, but not in both cases.</platformCore:message>
          </platformCore:statusDetail>