grey color scheme problem

Hello everyone, i use AUTOMATIC 1111 webui, and i have this problem. My image got the grey scheme at the end of the generation and the quality, deatils etc are really bad. I use optimized SD, vae-ft-mse-840000-ema-pruned.ckpt as VAE. Please help me if you know how to fix this problem, it's been days since i tried ti fix it and nothing work.

That is the blured thumbnail at 99% of generation, so i thought the grey scheme come at the last steps, so i installed anti burn extension, but the problem still persist.