Technical issues can mean white balance - but I don't think this is major problem. However, you have shadow areas under the hair and by the face which are clipped - no detail in these areas. If you look at your histogram and have clipping showing, you will see this - e.g. in Lightroom. Or, if you use camera raw filter in Photoshop. This could be a problem. The eyes also don't seem to be very sharp and you would definitely want them sharp!
Just a few more concerns, the background is a mess. Yes, I know it speaks to the school setting but let the buyer decide that. Did you send a model release with it? One eye, on the left, is not sharp. Sometimes I have a lace pattern in the foreground as the dress is in this one and for some reason, it gets rejected. So, overall not quite up to Adobe standard. Best regards,JH