You should be able to opt-out of your materials by following the instructions from the CU Book Store here.
You can verify that you have opted out of a particular material by locating the “lock” icon next to the material’s title.
If you are seeing your opt-out choices reset and the lock icons disappearing from materials on your “My Course Materials” page, this may be due to an ongoing issue with opt-out choices. The RedShelf team is currently working on preventing this unexpected behavior.
If you want to report any issues with opting out of materials or ensure that your selections are confirmed, please contact RedShelf so they can investigate further.