To change how you get verification codes:

When you sign up for 2-Step Verification, you’ll be asked if you’d like to get your verification codes by text message or voice call. However, you can always switch between the two options if you change your mind later.

To change how you get verification codes:

• Sign in to My Account .
• In the "Sign-in & security section," select Signing in to Google.
• Choose 2-Step Verification.
• Next to the 2-step verification number you'd like to change, select Edit Edit.
• In the bottom of the window that appears, select Change Phone.
• Next to, "How do you want to get codes?," select the option you'd like.
• Select Try it.