Leprechaun

If your Leprechaun is running around fast constantly, it means you left your Springfield before he stopped running from a previous tap. You should be able to tap on him and he will run for the usual 5-6 seconds more then go back to normal. The tricky part is actually tapping on him while he is running, he's a fast little bugger. Alternatively, I think you should be able to store the Wishing Well and then replace it in you town to put the Leprechaun in storage and the back on the streets.

Thanks for the replies. I had tapped him and even stored him once, but he kept going. Just now I managed to tap him a couple of times and he paid, but didn't slow down. I guess that's good enough

At least when it happend to me he kept running after I tapped again. But it was just for the normal duration then he slowed down.

Also, maybe try a reinstall.