Q&A Is ‘Sleep Masturbation’ a Thing?

My wife says I’m masturbating while asleep, though today she’s says I’m awake while it’s happening. I’m finding this very difficult because at no point since she’s been saying this have I woken up to find myself masturbating. I’ve haven’t woken up with my hand in my underwear. I haven’t woken feeling the effect on my penis of having been held and rubbed. I haven’t woken to an ejaculation. I haven’t had any kind of evidence that I’ve been masturbating. I’ve asked my wife to film me with her phone but she says that as soon as she moves I stop. So I have no evidence apart from her comment that she feels me doing it. She hasn’t told me that she’s seen me doing it; just that she’s felt me doing it. I'm not dismissing it and saying it isn't happening, I'm just saying I have no knowledge of it. I'm well aware my word doesn't count for much as the unfaithful spouse, but I’d like a little help please. If I am masturbating in my sleep, I don't know what can be done about it. If I am masturbating while genuinely asleep, I don't know if I’m sinning. I can't tell if my wife is imagining or dreaming it. If my wife is imagining or dreaming it, I would like to know what can be done about it.