Reference from Smartobject return different mapping in running process instances

Hi, I’m having trouble on how to permanently fix this problem.

In my workflow i used a smartobject to create references to be used on an approval system. In k2 Designer, i set the task user to username in the references, picture below:

after that then i deploy the workflow to test it. However what happened is that it uses a different mapping than what it supposed to be. picture below:

this is the JSON data that is returned: 

[
  {
    "Username": "jarjit",
    "ApprovalNo": 0,
    "Nik": "2024",
    "FullName": "Jarjit",
    "Email": "jarjit@gmail.co.id",
    "PositionCode": "TRBA1",
    "PositionName": "FINANCE PAYMENT UNIT HEAD",
    "BranchCode": "00",
    "BranchName": "HO",
    "companyCode": "FNCE",
    "menuCode": "CMT1124",
    "paramDateExp": 72
  }
]

It used the positionCode data instead of username.

Is there any solution / fix for this particular problem?