Verify in app purchases are enabled if restore all function is not working.
How to enable:
1. Go to “Settings” then “Restrictions”
2. Check that in app purchases are enabled. If not, enable them and repeat the restore all procedure.
Steps to Access:
1. Verify you're on the same iTunes account you used to purchase subscription.
2. Click "Library" button in the menu bar.
3. Click "Missing Issues" - top left side
4. Select "Restore" - now re-download issues.