You will get an error if Flash Fill cannot find the pattern. The first thing to check is that you're using Flash Fill close to the source data (e.g., in the adjacent cell). For instance, it won't work ...

Inserting and customizing the timeline chart . It's now time to insert a line chart, which you'll adapt into a timeline chart. Select the Date column (including the header ...

When creating a user through the Quick Actions menu, a subscription link is copied, but the domain is missing. Go to the Dashboard page. In Quick Actions, select Create User and create a user. Check ...