Calendar - Monthly Layout - Problem with Calendar legend

I have the Calendar - Monthly Layout setup as a menu item with default options. Under Themes the "Show Calendar Legend" is set to YES.
The Calendar correctly displays the event Categories in the Legend. If I click on a legend item it sometimes correctly displays the relevant events but other times it gives an error when there are events in the Calendar that should be displayed. Attached are screenshots of the Calendar and error when ramble was clicked.

Do you have any ideas on what could be causing this behavior?

Noel Adams.

Hello Noel

For this, I will have to check it directly on your site. Could you please submit a support ticket sending us:

- Super admin account of the site
- Link to that calendar page
- Tell me what category I need to click on to see this error

I will check to see what's wrong and get it sorted

Tuan