Okay, got a couple of suggestions for ya.

I recently bought one of those off candles that are supposed to be like super good. I haven't had a chance to try it out yet but I'll give you an update as soon as I do.

Also, and this is just a wild guess but no one else has suggested it so here it is. The way my grandmother keeps alot of the unwanted flying pests away from her flowers is that she mixes up a solution of horticultural oil and insecticidal soap and applies it to most if not all the flowers. Basically gardening is her life so she's out there damn near every day. But it would seem to make sense that if you used one or the other or a combo of the two and then applied it to your skin that would help as well. Both the horticultural oil and the insecticidal soap are available in non toxic solutions that can be applied to edibles (tomatoes, cucumbers, etc.) up to the day of harvest.

Like I said, that's just a wild guess. I've never heard of anyone really trying to use that as a mosquito repellant so it's basically all theory. But maybe it's worth a try if you can't think of anything else