UIView.animateWithDuration not animating after initial animation - swift

Question

I have two methods:
private func showPicker() {
UIView.animate(withDuration: 0.3,
animations: {
var pickerFrame = self.vPickerWrapper.frame
pickerFrame.origin.y = self.view.frame.size.height - 300.0
self.vPickerWrapper.frame = pickerFrame
self.bIsShowingPicker = true
self.view.layoutIfNeeded()
self.view.updateConstraintsIfNeeded()
})
}
private func closeThePicker() {
UIView.animate(withDuration: 0.3,
animations: {
var pickerFrame = self.vPickerWrapper.frame
pickerFrame.origin.y = self.view.frame.size.height + 1
self.vPickerWrapper.frame = pickerFrame
self.bIsShowingPicker = false
self.view.layoutIfNeeded()
self.view.updateConstraintsIfNeeded()
})
....
the first method is called when the user touches a text field that requires them to populate from the pickerview. The second method is called when either the close or select button is touched within the wrapper.
The wrapper is created in storyboard and has constraints (trailing, leading bottom) to position it off screen. I initially made the bottom constraint a IBOutlet and wanted to change its constant to handle the animation. (Which I do with other objects in this VC). I then tried to work with CGAffineTransform.translate and .identity and finally dropped down to working with the frame. In all three cases the wrapper will display but not close (move back off screen).
Here's the value of vPickerWrapper after I set its frame to pickerFrame:
pickerFrame CGRect (origin = (x = 0, y = 668), size = (width = 375, height = 300))
which is what I am expecting, just not any animation in the sim. The view never moves. Any idea why the display is not showing it in the new coordinates?