There is either an error in the cls_pres_harper.2da file OR an error in LORE which is causing you to be mechanically unable to take the PrC when you level.
According to LORE, prior to taking the class the character needs to have 4 ranks in persuade, 4 ranks in search, 6 ranks in lore, and 8 ranks in listen, plus the alertness and iron will feats.
In the 2da file I reference above, the character needs to have 8 ranks in persuade, 4 ranks in search, 6 ranks in lore, and 4 ranks in listen, plus the alertness and iron will feats.
Your character has 5 ranks in persuade, 5 ranks in search, 6 ranks in lore, and 13 ranks in listen, plus the alertness and iron will feats. So overall you are short 3 ranks of persuade.
Since you meet the requirements from LORE but not mechanically per the 2da file, the game will not allow you to level. It needs to be determined that the error is in the 2da file or if it is in LORE so we can fix one or the other (and your character, who was obvioulsy just following LORE).
Hope that helps.
-osX