Delay in unlocking Apple Account after password reset on new iPhone

Review the information provided here for the steps in Account Recovery. The email should arrive with the time you will need to wait before recovery within 72 hours.

How to use account recovery when you can’t reset your Apple Account password - Apple Support

Also note the cases where your Recovery request will be cancelled:

• Regardless of how you started the account recovery request, you should turn off all other devices that are currently signed in with your Apple Account until account recovery is complete. If your Apple Account is in use during your request, your account recovery will be cancelled automatically.
• If you started your account recovery request with iforgot.apple.com through your device’s browser, you should avoid using that device during this period. If possible, turn that device off. Using that device might cancel account recovery.