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. One is to do it manually. The other is to use the plug-in. 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 option is to install the plug-in Ties into Second Ending.
- To install the plug-in, open a score in Sibelius and choose File > Plug-ins > Install Plug-ins.
- Choose Notes and Rests and select “Ties into Second Endings”.
- Install the plug-in.
- To add the ties enter the notation in the second ending. Select the second ending and run the plug-in.