So I’ve used the console command according to your suggestion, but the result is still the same as this.
Then I’ve tried without using IES and using the default spot light from UE. pretty good, but still looks like screen space reflection.
I also tried this console command, r.Lumen.Reflections.ScreenTraces 1 to 0. The screen space effect is completely gone but all the emissive light is completely gone in the shower room.
What do you all think? what do I have to do? but to replace IES already includes a good solution. Thanks