If this is a 1923 note which is most likely the case you really need to check the color of the seal on the right of the note below the serial number. If the seal is black, you've got one of the most common ones and it will be worth around $27 also the serial number will start by D. On the other hand if the seal is purple (also the serial number will start with C) then you've got a really good note with a value of $400.
Hope this helps