Noisy Emissive Neon on wall

[mmflame]

Hello,

I try to create a scene , a Neon logo (Emissive) But I have noise a lot in reflections on the wall (keep flickering)

.
I use Lumen for GI and Reflection as you see in screenshot.
The Emissive parameter set 5.
How can I fix this?

Thanks.

[mmflame]

any suggestion?