What should I do if the Copic Ciao cap gets stuck and cannot come off the marker?

In this case you can try the following: 1. If there is no ink on the inside of the cap, simply try turning it - there is a chance it may come off. 2. If you see ink on the cap, it may be possible that the ink has hardened and made the marker difficult to open. In that case, put the marker in hot water (about 60 degrees Celcius/140 degrees Fahrenheit) for about 2 minutes, and then try to turn the cap. If you leave the cap with ink on it, the ink may harden and make the marker difficult to open. Because of that we recommend that you clean the caps of your markers regularly using a tissue soaked in Colorless Blender.