I'm hoping this is a fairly simple one. I've inherited a calendar with Calendar Overlays. A new calendar has been added 'ITSM' has been added, but the key color doesn't show when an item is added. It should be pink but is showing up as green. Screen grab attached.
I checked it out on my end and everything works fine. Not sure what you're missing:
Created a calendar & added events.
Created a second calendar and added events.
Created a view on the first calendar and then added the overlay of the second calendar.
Copied the URL of the new calendar overlay view and added it to the left nav.
Clicked the link and all colors in there and it works.
Check your link to see if it matches the link of the view you created. I suspect the link in your navigation is pointing to the default calendar and not the view.
Check and see it there is any embedded HTML to customize the color scheme. I followed the instructions on the article below and it voided any color changes I made to the calendar overlay.
There are mutliple ways to do this, so if it's not embedded in an HTML web part the page may still have a custom color schema. this article shows explains an alternative way to do this: