Help! Is this fat or loose skin?

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Hi I am trying to figure out if this is extra skin or fat. My weight has fluctuated in the past but since lifting the last few years I have started to grow muscle and keep fat off areas. I eat clean and do hiit a few times a week and lift 5-6 times a week and I can’t tell if this stomach issue is fat or skin. As you can see my belly button kind of sags too.