Can't see rise and set times on the timeline

If you can't see the timeline (which shows rise, set, transit, moon phase and twilight events), it's almost certainly because either

1. It's been hidden
2. Geodetics mode is enabled

You can read how to exit geodetics mode here: How do I exit Geodetics Mode?

To unhide the timeline (assuming you're not in geodetics mode), simply swipe up on the altitude chart, as shown:

You can hide the timeline again by swiping it downwards: