Instagram Help Center

To change the phone number that receives text messages (SMS) for two-factor authentication:

1. Tap or your profile picture in the bottom right to go to your profile.
   
2. Tap in the top right, then tap Settings.
3. Tap Security, then tap Two-Factor Authentication.
4. If two-factor authentication is already on, tap next to Text Message to turn it off.
5. Tap Turn Off to remove two-factor authentication from the old confirmed phone number.
6. Tap next to Text Message to turn on two-factor authentication again.
7. Instead of entering a code, tap Change Phone Number below the Next button.
8. Enter the new phone number and tap Next.
9. You'll be sent a text message (SMS) to the new phone number with a special 6-digit security code. Enter the code that was sent and tap Next.
10. You'll see a list of recovery codes. Tap Next to complete the two-factor authentication process.