Is it possible to treat collapsed gums?

My gums got really damaged after getting braces twiceㅜㅜ

Black triangles are appearing, and my teeth are also hurting frequentlyㅜㅜ

My gum swelling was severe, but it got a little better by using the Waterpik every day.ㅜㅜ

Is there no way to regenerate the already formed black triangle?

I'm 고민 whether I should get gum reshaping!