These issues seemed to have started after updating to iOS 10. Keyboard randomly freezes, forcing the user to close all open applications from the App Switcher feature and then reopen it. For several people, these problems have been frequent and have forced them to take a trip to the Apple Store to resolve this issue.
If you are a user who has experienced this problem, then we have some solutions that can help you fix the problem of freezing keyboard on your iPhone
The first thing that you must try to update to the latest iOS firmware and usually fix bugs present in previous versions. At this article, the most recent iOS firmware are iOS 10.0.2.
Update Your Device to latest version
How To update your iPhone, Open the Settings app and go to General -> Software Update and press the install button to update your device.
Force Reboot or Restart your iPhone
How is quite easy, you just need to press the home button or the sleep/wake simultaneously until the screen turn black and then the Apple logo appears. When the Apple logo appears then immediately release all buttons
Disable Predictive Keyboard Feature
Predictive typing is a small bar will appear above the keyboard phrase iOS and displays a suggested word. To disable this feature, please sign in to the app Settings - then to the General - and Keyboard. Scroll down until you view a button to switch predictive labeled. Switch to off to disable the predictive keyboard.
Reset All Settings
Step 1: Please open Settings app and then select the General section.
Step 2: Scroll to the end until you find the section press Reset.
Step 3: Next, please select "Reset All Settings, " and iOS will prompt you to enter the passcode. Dont Panic!, because this will not erase any data from your device. That will reset your device settings. Reset All Settings
Reset All Setting is a method that is mostly done by the user to fix the problems found on iOS devices.