Jon reached out and touched Zoe's hand and said "Swap." But nothing happened. Jon was still fifteen years old. And his sister was still seventeen.
Zoe yanked her hand back. "What the fuck are you doing?"
"I wouldn't let Mom catch you talking like that," Jon warned. Why didn't it work? His wish was clear. He should have been able to swap back. Maybe it would take a few tries to do it (since the swaps were random), but eventually he'd be able to get back to normal.
"I can talk however the fuck I want. Now get out of my way!" she said, pushing past Jon and into her bedroom.
Jon sighed and walked back into the bathroom. In his excitement, he must have left the stone in there. Once inside, he reached down and grabbed the stone. Fortunately, it was almost directly behind the toilet. Someone would only find it if they were looking for it.
"I wish to know why my last two wishes aren't working right," Jon said. The stone glowed and suddenly the information appeared in his mind. Apparently, the ability takes some time to recharge before another swap can occur. Also, the stone told him that there was no way around this, even though he hadn't specified it in the wish. There was no way to have his ability without recharging. According to the stone, Jon had to wait a minimum of one hour before being able to swap again.
What was he going to do for an hour?