Sometimes the roses can be air locked in the old tips. A tip is to take the roses out of the vase and cut the stem, place the tip of the cut end in boiling water for 30 seconds. Remove from the water and re-cut at a 45 degree angle and place in cold water.
For more help on caring for your flowers, please visit Flower & Plant Care Tips
After half an hour you should notice the roses to perk up. If they don't start to pick up please contact customer services on 020 3696 1136.