Group calendars and individual artist calendars are completely independent. Seeing an event on an agency or group calendar tells you nothing about whether it reached a particular artist — an event only lands on an artist's calendar if that artist is attached to the booking.
Check the artist is on the booking
Open the booking.
Go to the booking's Change tab.
Look at the artists listed there. Being part of a group, or being on your roster, is not enough — the individual artist has to appear on this list.
If they're missing, add them to the booking from the Change tab and save.
The calendar event is written as soon as the booking is saved, so refresh the artist's calendar and the date should be there.
If the artist is already on the booking
Go to Settings > Calendar & Templates > Calendars.
Search for that artist by name rather than scrolling the list.
Confirm a calendar is actually linked to them. An artist with no linked calendar will never receive events, even when they're on every booking.
If nothing is linked, link their calendar there. If the calendar belongs to the artist rather than being created from Gigwell, they need to share it with your agency's linked Google address at the Make changes and manage sharing permission level first.
If that doesn't work
Create a short test booking with just that artist attached and watch whether the event appears. That separates a linking problem from a lineup problem in one step.
Still nothing? Start a chat from the messenger with the artist's name exactly as it appears on your roster, and whether their calendar was created from Gigwell or shared to you by the artist.
Good to know
Calendar writes happen essentially instantly. If a booking was created minutes ago and the event isn't there, nothing is queued up catching up in the background — it's a linking or lineup issue, and the two checks above will find it.
When a lineup changes, swap artists from the booking's Change tab. That's what updates the calendars on both sides.