where can i change header text & Sub header text of my Custome page
 

Can anyone tell me how can i change the header & subheader text of my custome paege i'm trying the following code but its not working
;program

Page custom after_repair after_repair_leave
...
...
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function after_repair
!define MUI_PAGE_HEADER_TEXT "Ready to Repair the Program"
!define MUI_PAGE_HEADER_SUBTEXT "The wizard is begin installation"

functionend

!insertmacro MUI_HEADER_TEXT as seen in Examples\Modern UI\InstallOptions.nsi.