Hi Ruth,
Thank you for leaving us a review on Flawless, sadly it does sound like you needed to go up one more cup size in this style or it may be the fact that a plunge style bra is not suited to your shape, if a bra fits well you should not be rolling out of the middle when bending down! I can see that you have emailed us but never to ask for fit advice, if you are ever unsure we are always happy to help you find the best fit x