I can't send apple cash anymore to my son

Apple ID

If you can't unlock your Apple ID

If you use security questions with your Apple ID, or if you don't have access to a trusted device or phone number, go to iforgot.apple.com. Then you can unlock your account with your existing password or reset your password.

If your Apple ID is locked or disabled - Apple Support

Apple Cash

If your account is restricted, you can still transfer your Apple Cash balance to your bank or use it to make purchases in stores, within apps, and on the web. If your account is locked, you can't use Apple Cash to make purchases; add, send and receive money; or transfer the money in your account.

If your Apple Cash account is restricted or locked - Apple ...