abelbarrientes , Did a search on your issue and found this from forum link below for you to try. If this does not work may have to try a factory reset.
Try this: Under Settings > General > Apps > ALL (scroll left of DOWNLOADED/RUNNING options near top)
you will find "LG Keyboard" and a button that says STOP and CLEAR DATA, (click stop, then clear data).
See forum link below. Good luck.
I hope this helped you out, if so let me know by pressing the helpful button.
http://forums.androidcentral.com/ask-question/415536-lg-keyboard-has-stopped.html