Q: Instagram won't let me edit my profile information on the app or computer.

See the remaining items of:

iOS: Troubleshooting applications purchased from the App Store

Contact the developer/go to their support site if only one app.

Restore from backup. See:

iOS: How to back up              

Restore to factory settings/new iPod

Even i get this error.. In my case the app freezes when i scroll down in edit profile   I haven't changed my bio for so long

See:

If an app you installed unexpectedly quits, stops responding, or won’t open

Contact the developer/go to their support site

Restore from backup. See:

How to back up your devices using iCloud or iTunes

Restore your device from an iCloud or iTunes backup

Restore to factory settings/new iPod

If you want to edit ypir profile than i have another way in which you can do it.

Its simple! Just go to instagram.com amd log in and than edit ir profile from there!