Babywearing help- no matter which wrap or sling I use, baby ends up chin to chest, how to avoid?

I have a ring sling, a Moby, and a Baby K'tan. My lo is a month old and so I can only use the cradle hold or the newborn hug hold (Moby and ring sling)/kangaroo hold (K'tan). I try starting her out upright in the hug hold/kangaroo, and flat in the cradle hold, but because the sides of a wrap or sling are curved she always ends up curving towards herself and I can't fit the two fingers between her chin and chest like you are supposed to be able to. I can see her face but in the warnings the way I understand it it sounds like her airway could be blocked from inside even with her face visible, if her chin touches her chest. I am wearing it high and tight enough and have the right sizes and so forth. I have watched videos but we start out in the right positions and quickly squirm into the bad curved position instead. But when she rides in the car in a carseat, or spends ten minutes in her swing, her chin always ends up touching her chest because she is not old enough to do otherwise yet unless she is laying flat. Given this, what I can't understand is how do you keep a newborn's chin from touching their chest in any wrap or sling since they can't lay flat in one? I really, really need to use the sling or wrap because she needs to be held almost constantly and I need to be able to wash diapers, get a sandwich or bowl of cereal, grocery shop, etc. Also I have $150 into wraps and slings at this point and I would like to feel comfortable using one for more than 10 minutes by which point she has scrunched up chin to chest. Help, please!