As I know, the deleted data still store in iPhone, if they are not be overwritten, you can restore iPhone data directly, but you need some iStonsoft iPhone Data Recovery
programs for help, this way is for the user have no backup, if you backup your data with iTunes before, then recover deleted data from iPhone will be simply, , follow the step.Click the File menu and select Devices > Restore from Back up.
Or Open the iOS device's Summary tab. There are two ways to access this:
Click the device button in the upper right corner. (If viewing the iTunes Store, click the Library button in the upper right corner. The device button will then be visible.)
From any view in iTunes, click the View menu and select Show Sidebar. Select your iOS device in iTunes under Devices.
Click the Restore Backup button.
Guide:How to restore iphone lost call history.
Step 1. Switch to Recover from iTunes Backup File Mode
Step 2. Select to Extract iPhone Call History
Look more article:
How to restore iphone deleted call history
How to get lost data back to iphone