Hi elise83schuster
welcome to the Apple (user-to-user) Community.
Re: I am trying to get a verification code to erase my daughter's phone from my account
Am no expert in this area, yet your questiion to the community certainly deserves an answer.
It is not clear whether you want to erase your daughter phone for her,
or
whether you want to remove your daughter's iPhone from the list of devices in your own account.
Seems you can not get a verification code for anyone else's Apple ID account on your iPhone.
If your daughter has another Mac or device listed in her Apple ID account you could get a verification code on that: Get a verification code and sign in with two-factor authentication - Apple Support
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As you "don't have access to her phone as it won't work"
In the article below:
See Step 5: says:
"If you have AppleCare+ with Theft and Loss, do not remove the device from Find My or your Apple ID".
Else you can: "Remotely erase your device" (see the link in the article below for how to erase.)
Step 7 says:
If you have AppleCare+ with Theft and Loss, do not remove your lost iPhone from Find My or your Apple ID until your claim has been approved.
or
Go to appleid.apple.com to remove the missing device from your list of trusted devices. (NB: "more info". below)
Above is from: Apple support's article: If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support
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More info: Scroll to see how to: "Remove a device from the list":
in
Apple support's article: Check your Apple ID device list to find where you're signed in - Apple Support
All the best :-)
