Creating Customer - what am I doing wrong??

Hello,

I'm trying to very simply create a Customer record. The script is on a button, on a customer record. When it's clicked, the following code is called:

 try {    var record = nlapiCreateRecord('customer');      //set basic info    //set name    var name = prompt('Enter the name of the subcustomer:');    record.setFieldValue('entityid', name);    record.setFieldValue('companyname', name);    //set parent    record.setFieldValue('parent',nlapiGetFieldValue('entityid'));      var id = nlapiSubmitRecord(record, true);    alert(id);   } catch(Err) {    alert(Err.message);   }

I keep getting an error upon nlapiSubmitRecord. It simply says "undefined".

What am I missing here??