Improper Light
The most likely reason your Callisia is fading is due to a lack of light. Your plant prefers bright indirect light. If it is placed in a lower light environment, its colors will fade.
If you suspect your plant is fading because of its access to light, take a look at your space and find a sunnier spot. A window sill or sunny shelf is perfect for the Callisia to show off its gorgeous trailing vines.
Time for a check-up
Now is a great time for some TLC. Before you move your plant to its new spot, check in with it to see if it needs a trim or if it could benefit from a good soak.