Use of a solid white BG and the rule of thirds works well. Model pose is all right.
Exposure generally OK but not outstanding. Composition is fine. Color looks OK to me on this monitor.
Lighting is weak and looks to be 'flat' overall.
Sharpness, or the appearance of sharpness, is curious in this particular image and, unfortunately, probably hurts it. There are some high contrast small overexposed 'spots' on the lips that appear oversharp, yet most of the rest of the image looks 'soft' focused. Some facial blemishes should probably be removed. That confuses the visual viewer.
It looks like you applied noise reduction and it showed up in some areas more than others. That gives the image an unbalanced sharpness quality that many viewers will notice and not like. It seems smooth and unfocused in some areas yet oversharpened in others.
The image looks a little 'flat' contrast-wise.
Obviously it meets the challenge. But in a challenge like this viewers expect perfect technicals and/or a unique interpretation... they get neither in this image.
Focus on the technicals. Work on the issue of sharpness. If you used noise reduction then increase or decrease width of sharpening to either allow the image to be sharper or softer overall. If softer, avoid making your model look 'plastic'. If sharper, don't oversharpen.
Increase contrast and/or brightness to give the image more viewer interest and impact. Add vignetting and or dodge and burn to highlight the model and or add more viwewer interest to the overall composition.