Not receiving the verification code

Hi there, david51. I understand your frustration with not receiving the verification code despite having the correct mobile phone registered in QuickBooks Online.

I want to assure you that we are aware of the problem, and our dedicated engineers are currently working to determine the root cause and implement a permanent solution. 

While I cannot provide a specific timeframe for when the issue will be resolved, I recommend contacting our Support Team for the most recent updates and assistance. But since you're unable to login, you can use the phone number provided in this link to reach them: Contacting QuickBooks Support.

To learn more about multi-factor authentication and two-step verification, please refer to this article: Secure your Intuit Account and prevent lockout with extra verification methods. 

Your patience and cooperation are greatly appreciated as we work towards resolving this issue promptly, david51. I'll be checking this thread for your response if you still have questions or other concerns about QuickBooks Online. Have a great weekend!