X++ Code - Open CustOpenTrans form

hi,

I'm trying to create a job to open "CustOpenTrans" form but whenever I declare args.record() to a specific customer, it tends to select all customers and takes a long time to open the form. How can I pass args to the form to only the specific customer

Below is my code: 

static void OpenFormByCodeB()
{ Object formRun;
Args args = new Args();
;
args.name(formstr(CustOpenTrans));
args.record(CustTable::find(AccountNum));

formRun = ClassFactory.formRunClass(args);
formRun.init();
formRun.run();
formRun.wait();
}

thanks!