UIView.animateWithDuration not animating when called inside keyboardWillShow - objective-c

Question

For some reason my view is not animating:
- (void)keyboardWillShow:(NSNotification*)aNotification
{
NSDictionary* info = [aNotification userInfo];
CGSize kbSize = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
double duration = [[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
int curve = [[info objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue];
int height = self.view.bounds.size.height - kbSize.height+self.tabBarController.tabBar.frame.size.height;
self.notesView.frame = CGRectMake(0, -height,
self.view.bounds.size.width, height);
[UIView animateWithDuration:1.5 delay:0 options:curve animations:^{
self.notesView.frame = CGRectMake(0, 0, self.view.bounds.size.width, height);
} completion:nil];
}
The notesView is being displayed but not animated. When I move the animation code into a btnPressed method then it animates as expected. Any ideas?
Edit
It looks like the method is being called twice (that's a separate problem dealing with the inputAccessoryView that I still need to figure out). I updated it to see if calling the animateWithDuration code only once would solve the problem. However, it's still not animating.
- (void)keyboardWillShow:(NSNotification*)aNotification
{
NSDictionary* info = [aNotification userInfo];
CGSize kbSize = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
int curve = [[info objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue];
int height = self.view.bounds.size.height - kbSize.height + self.tabBarController.tabBar.frame.size.height;
if (height == 510) return; //for some reason the self.view.bounds.size.height is different between the two calls
self.notesView.frame = CGRectMake(0, -height, self.view.bounds.size.width, height);
[UIView animateWithDuration:1.5 delay:0 options:curve animations:^{
self.notesView.frame = CGRectMake(0, 0, self.view.bounds.size.width, height);
} completion:nil];
}