I recommend a decent batting coach. We figured that out in DD's second year of 10U TB. Coaches don't have the time to teach every girl on the team the proper way to hit.
Most girls in Texas TB go to a batting coach some our pricey some are reasonably priced. My DD goes once a week for one hour and our coach actually starts out the session hitting off the tee tweaks in her swing than we move on to either soft toss or machine. She has gotten rid of all her bad habits and now has built her muscle memory for the correct swing. It took a few months for that.
Hope this helps