I am using a form client script.  I am trying to the change the value of a field in a sublist. I can tell the script executes, but does not set the value

Is this correct?

if (context.fieldId == 'location' || context.fieldId == 'quantity') {
       
            Object.keys(context.currentRecord).forEach(function(key) {

//            alert('key:' + context.currentRecord[key]);

            }); //**************for each function**************
           

            context.currentRecord.setCurrentSublistValue({      sublistId        : 'item',
                                                       fieldId        : 'quantity',
                                                      value        : 12 ,
                                                      ignoreFieldChange: false        });

            var sublist = 'Sublist: ' + context.fieldId;
            log.debug('Field Changed: ', sublist);
//        log.debug(        'Field Change',    'Sublist:' + context.sublistId + ':' + context.fieldId );
        alert('Sublist:' + context.sublistId + ':' + context.fieldId);