iPhone keyboard keeps jumping back and forth

Sorry, that’s not enough information to help you diagnose the issue. If you will please provide more details such as iPhone model and iOS version you’re using and when it happens and what apps.

Try a forced restart as a general cure all.

Force restart iPhone - Apple Support

If Jeff's good advice does not solve the issue, then please



• Tell us which model iPhone you have and its iOS version
• Offer as many details as possible about the problem. What were you doing or trying to do when this happens? 
• List any trouble shooting steps you have already tried. 

We want to help if we can.