Emissive material flickered in still render

**D5 Render Version:2.10.1.0579
**Graphics Card:NVIDIA 4070
**Driver Version:32.0.15.6614
**Issue Description: my recent file of this project, suddenly the emissive material caused flicker in the preview, and affecting the still render
**Screenshots/Videos Description:

before

**Steps to Reproduce (optional): If i turned off the cast shadow on the emissive material, it was better, but the light intensity and effect will be different

anyway to solve this?

Thank you!

Tommy