I am not receiving verification codes

From: Get a verification code and sign in with two-factor authentication - Apple Support

A code is sent first to your trusted devices automatically:

"If you have a trusted device running iOS 9 and later, OS X El Capitan and later, iPadOS 13 and later, or watchOS 6 and later, the verification code is displayed automatically on your trusted devices."

If you don’t have a trusted device handy, you can choose to have a verification code sent to your trusted phone number as a text message or phone call.

1. Click "Didn't get a verification code" on the sign in screen.

2. Choose to have the code sent to your trusted phone number.

3. You'll get a text message or phone call from Apple with your verification code. This text message might include an additional domain validation line. This line includes the @ symbol, the website name, and your code (for example: @icloud.com #123456 %apple.com).

4. Enter the code on your other device to complete sign in.

"If you can’t receive a verification code on your trusted devices automatically, you can get one from Settings, even if your device is offline."

On a mobile device go to Settings > [your name] > Tap Password & Security > Get Verification Code.

On a Mac: Go to Apple menu  > System Preferences [System Settings], then click Apple ID. Click Password & Security > Get Verification Code.

If you don't have, or cannot get access to, a trusted device, you can tap "Didn't get a verification code" and have it sent to a trusted number by text or voice.

"If you can’t sign in, reset your password, or receive verification codes, you can request account recovery to regain access to your account [ How to use account recovery when you can’t reset your Apple ID password - Apple Support ]. Account recovery might take a few days or longer, depending on the specific account information you can provide to verify your identity."

beatnation Said:

"I am not receiving verification codes on IPhone 12 Pro Max"

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Troubleshooting Two-Factor Authentication:

Set it Up Correctly: Manage Two-Factor Authentication for your Apple ID from iPhone - Apple Support



Verify your Trusted Numbers:

1. Go Here: How to Get Verification Code on New Phone after I Erased all my Stuff from Old Phone - Apple Support
2. Scroll to: Add or remove a trusted phone number
3. As it Reads: "If you can’t access any trusted devices when setting up a new device for two-factor authentication, tap 'Didn’t get a verification code?' on the new device, then choose one of your trusted phone numbers to receive the verification code."

Generally, those verification codes are sent using Short Code Text Messaging. These short code text messages are received from a 5 or 6 digit phone number. This capability/feature is provided and managed by your carrier. I recommend that you contact your carrier and tell them about not receiving verification codes which may be sent over short code messaging service. Their support team should be able to address this for you and find a resolution.

Axel F.