We need to know some information to help.
A. What version did you update from? 19 or 17? If 17 then you need to re enable and copy the tts, this is explained in the updating instructions from the 2.0 update page.
B. Did you do what the instructions said to do?
C. If you did do that, and it still doesn't work even though its selected as the language, did you restart the unit? Try switching it to the male english voice, jason, make sure it works then reselect symantha if its available, restart the unit, by either turning the car off or hitting the reset button. That should fix it. If its not available, see step A.