Last updated on December 4, 2020
If you find that someone has created an Instagram account pretending to be you, it can be reported to Instagram immediately for your safety. Therein, you are requested to provide all the necessary information, including a government-issued photo ID (e.g. both sides of National Identity Card for Sri Lankan).
If you have an Instagram account, you can report it to them within the app, or by filling out this form.
If you don’t have an Instagram account, please fill out this form.
Instagram responds to reports sent to them from the person who’s being impersonated or a representative of the person who’s being impersonated (example: a parent on behalf of their kid). Therefore, If someone has created a fake account for a friend of yours, please encourage your friend to report it.
Note: If you come across troubles uploading your photo ID from a mobile phone, please try to submit this form from a computer.
Source: https://help.instagram.com/370054663112398?helpref=search&sr=1&query=impersonating