How to blur confidential text on moving object

Hello Friends, I am planning to shoot the video where I will be giving demo of digital payment transactions using two smartphones. During this demo, there will be slight movement of both the smartphone and confidential text like (mobile number and name) will be displayed on the screen. I need your help in understanding the Adobe Premier Pro knob that can help me to blurr the confidential text on the screen of smartphone (subject to slight movement).

Any video or documentation link addressing this would be really appreciated.