My daughter at the age of 6 months had a cow milk allergy, so we switched her to soy formula. We had to wait at least 1 year before reintroducing any cow milk or cow milk products whatsoever--you are probably trying to introduce cow milk too early into her diet. Also, not every baby who has cow milk allergy is going to grow out of it--some have the allergy for life (I discovered at the age of 40 years that I had a casein allergy; it is hypothesized that I have probably had it since birth).
My daughter is currently not allergic (or not showing signs) to cow milk/cow milk products, but she has a very high propensity to reacquire the protein allergy at a later age in life (to either casein or whey. But knowing that both me and her dad are both allergic to casein, that is probably the one she is/would be allergic to as well).
Try giving your daughter other dairy items that are NOT cow dairy, like goat, sheep, and milk-substitutes like hazelnut, oatmeal, rice, coconut, almond, hemp, etc..
Oh, and I would definitely watch/switch her from soy. Soy has estrogen-disrupters for women/little girls and can make little girls go through puberty earlier than normal. I wish I would have known that 11 years ago; I never would have put my daughter on soy formula. I would have found something else for her to drink.
And it is entirely possible that your daughter is/will be allergic to cow milk forever. One way to know if she's allergic now is to see a naturopathic doctor and have the doctor do a saliva swab on your daughter; it will tell if she has a casein or a whey allergy.
If your daughter is still having issues with anything to do with cow dairy products/milk, I would keep her away from them. There are other alternatives out there; she doesn't need to drink or eat cow milk.