not eating enough.

[cypher]

She looks a really good size for her age tbh, if you can get some scales & just keep track of her weight it is a good thing to do anyway.
Getting good food for hybrids in the US isn't easy, the food you're currently using is too low in protein & fat although the mealworms will help with that, the fibre is higher than it needs to be as well which isn't so much of a problem in itself but does mean overall nutritional value is lower than it could be, the food also contains molasses & you really don't want any sugars in the mix you feed to a hybrid.

You can buy Burgess dwarf hamster harvest from viovet although it has to be shipped from the UK so works out a bit expensive, you could buy a few bags though & keep it in the freezer so it lasts a while if you chose to do that.
I always forget which US foods come anywhere close to being suitable so I'd have to check them all out again before suggesting anything else.