CABasicAnimation working on one image, but not another - ios

Question

I have the strangest problem with animating two identical UIImageViews. A separate event triggers these two UIImageViews being moved closer to another, which I animate in the following manner:
CGFloat originalX = self.firstMatchImage.layer.position.x;
self.firstMatchImage.layer.position = CGPointMake(originalX + displacement, self.firstMatchImage.layer.position.y);
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"position.x"];
animation.fromValue = #(originalX);
animation.duration = .18;
[self.firstMatchImage.layer addAnimation:animation forKey:#"position.x"];
CGFloat originalXsecond = self.secondMatchImage.layer.position.x;
self.secondMatchImage.layer.position = CGPointMake(originalXsecond - displacement, self.secondMatchImage.layer.position.y);
CABasicAnimation *animationSecond = [CABasicAnimation animationWithKeyPath:nil];
animationSecond.fromValue = #(originalXsecond);
animationSecond.duration = .18;
[self.secondMatchImage.layer addAnimation:animationSecond forKey:nil];
And this works just fine. The images move toward one another quite readily. However, I also have an event trigger an animation to make these UIImageviews move back to their original location. To do this, on the viewDidLoad method of my storyboard controller, I capture their base locations thusly:
firstImageOrigin = self.firstMatchImage.center;
secondImageOrigin = self.secondMatchImage.center;
So in the method call to move these UIImageViews back I do the following:
CGFloat originalX = self.firstMatchImage.layer.position.x;
self.firstMatchImage.layer.position = firstImageOrigin;
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:nil];
animation.fromValue = #(originalX);
animation.duration = .18;
[self.firstMatchImage.layer addAnimation:animation forKey:nil];
CGFloat originalXsecond = self.secondMatchImage.layer.position.x;
self.secondMatchImage.layer.position = secondImageOrigin;
CABasicAnimation *animationSecond = [CABasicAnimation animationWithKeyPath:nil];
animationSecond.fromValue = #(originalXsecond);
animationSecond.duration = .19;
[self.secondMatchImage.layer addAnimation:animationSecond forKey:nil];
Much to my displeasure, only the UIImageView called firstImageView moves back correctly. It works perfectly for the first image, but the second UIImageView(self.secondMatchImage), doesn't behave the same way, it animates and moves a little, but not back to its original location. here is what the result looks like:
I've played with naming the keyPaths something other than nil, but when I trigger a tap gesture, it crashed the app if I have named the keyPaths. I have tested this on an iPhone and the simulator - same behavior. I am super stumped here.
Any insight on how this is happening would be super great! Thanks!

Answer 1

So, turns out, grabbing the location of the images in the controller's viewDidLoad method was not the ideal solution. Instead, I set the original coordinates to
CGPointMake(0,0)in the viewDidLoad method and use this login in my animation method:
if (firstImageOrigin.x == 0 && firstImageOrigin.y == 0) {
firstImageOrigin = self.firstMatchImage.center;
secondImageOrigin = self.secondMatchImage.center;
}
And now it works perfectly!