How can I change the contact method for receiving verification code without calling customer service?

Let me help you use your email address in receiving the verification code @netprosync.

When you try to log in to your account using a different device or browser, it will prompt options to send the verification code, either by your mobile phone or email associated with your QBO account. 

If the email option is unavailable on the page, this is because your two-step verification is turned on. What we have to do is to turn off this setup. 

Here's how: 

1. Sign in to your QuickBooks Online account
2. Select the Intuit Account icon at the top right, then choose Manage your Intuit Account.
   
   
3. Click Sign-in & security.
4. Select the Two-step verification section.
   
   
5. Click the Turn off button.
   
   
6. Enter the password, then select Turn off two-step verification.
   
   

Once done, try to log in to your account using a different device or web to check if the Email a code option is available. 

For more insights about the process, please see this article for your reference: Verify your account with multi-factor authentication. It covers information about the importance and usage of MFA to your account.

In addition, let me share these links to help you manage your account in QuickBooks Online: 

• Change your email, user ID, or password for QuickBooks Online
• Change your business name, contact info, or VAT in QuickBooks Online

Hope that clarifies everything. Know that you can always get back to this post if you have other questions about verifying your account. I'll be happy to assist you again.