Instagram has ended the ability for users to log in via their Instagram account per June 29th 2020. This impacts Many.link as well.
For privacy reasons we initially didn't ask for an email address when you signed up for Many.link. But since March of 2020 we required you entered your email when logging in. You can now use this email address to get a link sent to you, which you can use to log in here.
If you DO NOT have an email address associated with your account, send an email to support with your username and we'll get back to you as quickly as possible with next steps.