This article refers to Reclaim 1.0 features and workflows. You can confirm your current app version in your User profile and view help docs for Reclaim 2.0 here.
Toggling a calendar coloring between Only Reclaim events and All events is a "heavy" operation because it may need to color code hundreds of events. Toggling it more than twice within a minute can cause issues.
To reset your calendar colors:
Navigate to the Settings > Colors
Set all colors for each category to Calendar color
Wait a few minutes for everything to settle on your calendar.
Set the colors back to their original values.