I have hyperpigmentation after CoolSculpting. Is this permanent? (Photo)

I had a chin coolsculpting procedure done on 29th June 2024. One day after the procedure, the area turned black and three days later the skin was peeled off. I am now left with a hug hyperpigmentation on my chin and ive used vitamin C, had two deep chemical peel and also have one dermabrasion. Since 8th september i started using hydroquinone.... I haven't noticed any changes since. I'm very upset about this and i don't even understand why my procedure went so horribly wrong. Any advice?