...then that means you installed TOB, the TOB patch, or a dialog.tlk overwriting mod like the Baldurdash Text Fix, TDD, etc. _AFTER_ you had other mods in place.
This is not good. Stop doing this.
This will basically require that you uninstall BG2, manually delete the BG2 override directory and the weidu.log file in your BG2 dir, then reinstall the game in the required order:
(Baldurdash if desired)
then and only then
(first the dialog.tlk overwriters, then WeiDU mods like ours.)
EXTRA CREDIT: After you install the Bioware patch, make a backup of the override directory, dialog.tlk, and chitin.key. Then, if you ever need to do a "full reinstall" all you have to do is erase the current override dir and replace it with the backup, replace dialog.tlk and chitin.key with your backups, and delete the weidu.log file. Time savings--probably at least 20 minutes.