Go to Settings > Security and lock screen > Enter Wallpaper slideshow to edit:
Tap Default list to preview and add/delete the photos in this list
Tap Types of subscriptions to select the preferred categories and download online wallpapers
Tap My collections to preview and edit the photos saved from online wallpapers
To add or to remove the wallpapers to/from lock screen slideshow, turn on / off the right-side switch of each list
Note: The operation steps/information in this FAQ may not be applicable to all types/series of Zenfone product. Some options in the screenshots and operating procedures may slightly vary, depending on the software and firmware version.