I have already a purchases ringtone installed. How do I replace it with another? I have an iPhone XS

Hi hagakyrkogata,

Thank you for participating in the Apple Support Communities. We understand your wallpaper photos are not rotating hourly as you've set them to do. It looks like you've come from the correct article for setting this up: Change the wallpaper on your iPhone - Apple Support.

1. "In the Settings app, tap Wallpaper.
2. Tap Add New Wallpaper.
3. Select Photo Shuffle from the top row of options.
4. On the Photo Shuffle screen, set a frequency (On Tap, On Lock, Hourly, or Daily). Then choose a set of photos that will shuffle as you use your iPhone throughout the day.
5. Tap Done."

If those steps aren't working, you may want to restart your iPhone or update iOS to see if the issue persists after doing so. Here's how if needed: Update your iPhone or iPad - Apple Support.

Take care.

What does the Title have to do with the content of your post?

Do you have a ringtone problem or a wallpaper problem?