How to Fix Instagram Two-Factor Authentication When You Can’t Receive Codes

I enabled two-factor authentication on Instagram about 4–5 months ago, and today when I tried to log into my account again, it asked me for a verification code. However, when I opened the Duo Mobile app, there was neither a code nor anything else; it simply redirected me back to the login. Please help—I’m unable to access my account of many years. It doesn’t give me a backup code either. I took a selfie through the “verify with photo” option, but this time it didn’t accept it. Please help.