that is the Record Selection formula in the pic. what is the formula for Current Date and what is the formula for the Expiration Date that you're trying to use in the Chart's Show Value?
what version of crystal reports are you using? are you using visual studio?...if so this may not be possible. if that's the case then you'd need to try this out in the full version of the crystal reports designer. you can get a trial here.
if you are using the full version of the designer then try creating a new chart instead of editing the existing one. sometimes you'll get weird issues like that if a chart has been edited many times.