There are a couple of reasons why your rolls may not rise. Yeast is expired. Always check the expiration date on your yeast. I keep my yeast stored in the freezer which will extend the life of it. Water temperature is wrong. If your water temperature is not warm enough the yeast will not activate. If the water is too warm, it will kill the yeast. Water temperature needs to be between 105-110 degrees F. It is like a nice warm babies bath water.