Some users have reported experiencing problems with their Safari. Users have tried to erase the history in Safari, but it appears grayed out. Deleting through the Settings also does not seem to work on the iPhone.
There is a good chance that you are experiencing this problem because of your “Restriction” settings on your iPhone 6. You can solve this issue by switching off your restrictions by following the steps outlined below.
Step 1. Open the Settings
Step 2. Tap on “General”
Step 3. Scroll down and Select “Restrictions”
Step 4. Enter your restrictions code when prompted for.
Step 5. Choose “Disable Restrictions”
Upon disabling the restrictions, you should be able to erase your history on your iPhone. If you only clear History and leave the cookies and data, you can still see all web history by going to Settings > Safari >Advanced (at the bottom) > Website Data. In order to clear the history, please use both the options i.e Clear History and Clear Data and Cookies.
If you are having other Safari related issues, please see our comprehensive guide on Safari issues for both iOS and OSX.