I might be wrong, but it looks like the infamous "jello effect" which is usually caused by vibrations in the drone causing a strobe effect with the video frame rate. If the vibration is caused by faulty props (or imbalanced props), an easy fix...
Your "Expo" settings have probably gotten changed. In main DJI Fly screen, tap the three dots in the upper right corner, then select Control, then select Gain & Expo Tuning, and adjust all three flight modes to your liking. Hope that helps!