ASP Spell Checker Problem:Spell check is happening but the change of wrong spelling is not taking place

Hi there,
I m using an asp spell checker in my application.the problem faced is that when i put some text in RichTextBox field and  then click on "spell check" button  It is prompting  for the spelling mistakes, but when we select correct spelling it is not copying it in RTB. 
 
Awaiting for reply
Thanks
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