If the band is riding up, it is not fitting you snugly enough. You may need a smaller back size.
If the straps are digging in this may be because the band is too big and not giving you enough support, meaning that the straps are doing all the work. – try loosening the straps too see how the band feels. If, with the straps loosened the band is not supporting, try a smaller band size.
The centre front should sit flat against the body. If the centre front is pushed away from your body the cups are probably too small, so try a larger cup size.
If the underwire is digging in or pinches the breast tissue under the arm, this is a sign that the cups are too small. It’s important that the breast tissue is completely held by the underwire, so try a larger cup size.
If your bust is bulging over the top of the cups, they are too small. Try wearing a t-shirt over the bra to show up any bumps.
If the cups look baggy try a smaller size.