You can find more context on my account here.

TL;DR: About a week ago, someone found my private NSFW account on another website, thought the characters I drew were children when I clearly stated they're adults, and they made a "callout" account on instagram.

They privated their account after I did something manipulative (self-harmed) and they never deleted the account. Now every time you look up my username, their account is the first thing you see, accusing me of drawing CP tied to my username.

I've tried reporting their account even before they privated, but since their account is private now, instagram basically said "we didn't see anything wrong, so we can't do anything." What do you mean you can't do anything about defamation of character explicitly written on their bio?! Instagram also suggested I report a specific post of theirs, but how the hell am I supposed to do that when their account is private now?

I'm stressed out. I'm anxious as hell. I want to cry. I can't stop thinking about it knowing it's there, in plain sight. They're basically passively ruining my life.

What can I do? Please, I need help. I'm losing my mind.