I've never seen your daughter's pullover, so I have no idea where the problem may be. It may simply be strength as gymnut mentioned. For these kids, we have them do their pullover with a block so that they can do the skill and feel successful while building the technique and muscles needed. Start with a block about 24" high and have her put both feet on top. Raise belly to the bar, then kick feet over. Then drop down to a 12" mat and try the same. Then, turn the mat perpendicular to the bar so that is sits under the bar. She should stand on one side -- the side of the foot that she steps on. The kicking foot should be opposite that mat. Put a mark about a foot away from the bar for her to step on. Have her try the pullover from there. Once that is easy, try it on the floor again.
If strength is not the issue, there are several things that may be going on. The most prevalent problem I see in pullovers is the head position. Our instinct tells us to throw our head back, but if you do that too soon, then it pulls your belly away from the bar. Instead, she should watch her toes get up and over the bar, then begin to pull the chest around. Another issue that I see, especially in this age, is the inability to finish the skill. They have difficulty rolling their hands around the bar and lifting the chest, so they just fall back off the bar. A simple drill is to have her get on the bar in a front support, hang over the bar (still holding on), then lift her chest back to front support.
The pullover is one of those milestone skills. It takes some kids a year to learn and frustrates many a young girl. Just keep encouraging her!
