Soft reboot the phone > Please hold the power button and the volume-down button for roughly 7 seconds. Let go of the buttons once you feel the device vibrate and see the Samsung Galaxy S8 logo on the screen.
Clear the Cache and Data of the Keyboard.
Check any relevant preference Settings in the keyboard.
Close the phone Down and clear the system cache. (Press and hold the Volume Up key and the Bixby key, then press and hold the Power key. When the green Android logo displays let go of all keys (‘Installing system update’ will show for about 30 to 60 seconds before showing the Android system recovery menu options). - Press the Volume down key several times in order to highlight “Wipe cache partition.” - Press the Power key to select. - Press the Volume down key to highlight “Yes” and press the Power key to select. - After the wipe cache partition is complete, “Reboot system now” is highlighted. - Press the Power key to restart the device.)