textfield won't resign

Hello,
I have a view with text fields which when one of them is pressed a UIActionSheet comes up instead of the keyboard. The problem is that when i press a diffrerent text field and the keyboard comes up and then press the textfield with the UIActionSheet, after I dismiss the ActionSheet the keyboard is still up and it creates a problem because it won't come down even if I change to other view.
I tried to use resignFirstResponder but nothing I did worked.... Can someone please help me?