Value not passing in JSON of WEB RFC

Hi Guys,

     I am currently doing POC on personas 2.0. I need some help, I am calling the web RFC from the Personas 2.0 and putting that in a HTML Viewer but the value i have in a variable is not updated into the JSON. I have given the ABAP Code below and screenshot of html Viewer. Please help me solve this issue. Thank You.

DATA: htmldoc LIKE LINE OF HTML.
DATA: wa_ekko TYPE ekko,
       lc TYPE STRING VALUE 4500000000.

   SORT QUERY_STRING DESCENDING.
   READ TABLE QUERY_STRING WITH KEY NAME = '_EB'.
   WRITE: QUERY_STRING-VALUE.
   LC = QUERY_STRING-VALUE.

   select SINGLE * from EKKO into CORRESPONDING FIELDS OF wa_ekko where EBELN = LC.

   CONCATENATE '{"results": [ {"key": "bukrs", "value": "' wa_ekko-bukrs '"}]}' INTO htmldoc-line.
   INSERT htmldoc INTO TABLE HTML.
ENDFUNCTION.