You can delete your call history so that none of your calls appear on the Recents list.
 This will display a list of recent calls that you've made and received.
 Red minus signs will appear next to each call in the log.
 Tapping the minus sign next to an entry will delete it.
 If you want to delete the whole list, tap "Clear" in the upper-left corner. This only appears after you've tapped "Edit." All of the entries in the Recents tab will be deleted.
Open the Phone app.
Tap the "Recents" tab.
Tap "Edit" in the upper-right corner.
Tap a red minus to delete a single entry.
Tap "Clear" to delete all of the entries at once.
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