block animation delay is not working - ios

Question

When this method is first called, it works good.
On second call, the delay does not work.
The other code works good except for the delay.
How do I solve this problem?
-(void)makeParticle:(id)sender{
Bubble *bubble=(Bubble*)sender;
CGPoint center=bubble.center;
NSInteger radian=arc4random()%360;
for (int i=1; i<=13; i++) {
NSInteger distance=20+arc4random()%80;
radian+=10+arc4random()%40;
UIImageView *iv=[[[UIImageView alloc]initWithImage:[UIImage imageNamed:[NSString stringWithFormat:#"star%i.png",i]]]autorelease];
NSInteger size=20+arc4random()%20;
iv.frame=CGRectMake(0, 0, size, size);
iv.center=center;
iv.alpha=0;
[self addSubview:iv];
[iv release];
[UIView animateWithDuration:0.4 delay:0.1 options:UIViewAnimationOptionCurveEaseInOut|UIViewAnimationOptionAllowUserInteraction animations:^(void) {
iv.alpha=0.5;
iv.center=CGPointMake(center.x+distance*cos(radian), center.y+distance*sin(radian));
} completion:^(BOOL finished) {
[UIView animateWithDuration:1 delay:0 options:UIViewAnimationOptionCurveEaseInOut|UIViewAnimationOptionAllowUserInteraction animations:^(void) {
iv.center=CGPointMake(600, 100);
iv.alpha=0;
} completion:^(BOOL finished) {
[iv removeFromSuperview];
}];
}];
}
}