Can I reuse my Graffiti 3D?

Yes but:

You can't reuse your Graffiti 3D's corresponding Wonderful Graffiti. We don't recommend reusing the double-sided tape on your Graffiti 3D. To reposition your Graffiti 3D precisely, you may want to reorder the corresponding Wonderful Graffiti to serve as another template. You can, of course, afix your Graffiti 3D directly to another wall with new double-sided tape but later removal of the tape may damage your wall.