In the example, below, there is a tie at the end of the bar before the first ending. Therefore, there should also be a tie leading to the note in the second ending.
There are a couple of ways to address this. The option I use most often is via the symbols menu:
- Select the whole note in the first bar of the second ending.
- Press the letter Z to open the Symbols menu.
- Click “More Options” as I find it easier to navigate this view.
- Go to Notes and choose either the above or below tie. In this case the below tie.
- Drag it as needed.
The other way to address this is using a non-magnetic slur. However, if takes more time to adjust the look of the slur. Here is the section of the Sibelius manual that mentions this.