follow doc 363298.1 made read only responsibility not working

Hello
I try to follow doc 363298.1 but i found error. please help me to solve it please

APP_MENU2.SET_PROP('FILE.SAVE', ENABLED,PROPERTY_OFF);
APP_MENU2.SET_PROP('FILE.ACCEPT', ENABLED,PROPERTY_OFF);
Error 487 at line 169 column 11
Invalid reference to variable 'APP_MENU2'
error 0 at line 169, column 1

---below code

  formname      varchar2(30) := name_in('system.current_form');
    blockname     varchar2(30) := name_in('system.cursor_block');
    APP_MENU2 varchar2(255);
   
  begin
    null;
    BEGIN

IF event_name = 'WHEN-NEW-FORM-INSTANCE' THEN
IF FND_PROFILE.VALUE('USER_NAME')='TRIAL' THEN

BEGIN
COPY('Entering app_form.query_only_mode.','global.frd_debug');
COPY('YES', 'PARAMETER.QUERY_ONLY');