Hi Rich,
Waiting longer may help if verification requests have triggered a temporary restriction, but since your son’s password is also not working, I would first separate the account sign-in issue from the Family group setup.
Please try signing in to your son’s Microsoft account directly at Microsoft account, without adding it to the Family group again. If the password is rejected or the verification code still does not arrive, use the Microsoft Sign-in Helper and follow the options provided for that account.
For now, avoid requesting multiple new codes, as repeated requests can prolong a temporary verification block. If another verification method is already associated with the account, such as a recovery email, try that instead.
Could you also confirm whether the missing code is being sent to verify your son’s account or your organizer account, and whether the displayed phone number ends in the digits you recognize? This will help distinguish an account-recovery issue from a Family invitation issue.
If the account cannot be recovered through the Sign-in Helper, you can contact Microsoft Support for account-specific assistance. This is a user-to-user forum, so contributors cannot inspect the account’s verification status or remove an account-side restriction. Thank you so much for your understanding.
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