My chicken is making this weird noise

For context

My Chicken has been sick for the past two days. I’ve posted about it so if you want more detail, just go to my page. The baseline of it is she has low energy. She showed signs of some mucus which shut her eye and some thick yellow mucus coming out of her nose, but now it’s better and her eyes is open and there’s no more mucus. She is also shown trouble breathing but also doesn’t have any more. Her comb has gotten a little bit lighter and I don’t know what they’re called but if you see the bottom left red things they are also getting lighter. I have given updates but this is just something that I couldn’t put in a comment so im putting it in a post instead.

If anyone knows what this is then it would be great if anyone had an advice and for people who I have already told about this Here is some video evidence of what it sounds like.

As always, thank you to anyone who has already given advice or to anyone who has any advice to give!!