Your Apple ID is compromised, she has changed your password and changed the trusted phone number
See this instructions on how to regain control of your Apple ID
- Change your Apple ID password
- If your Apple ID password has been changed by someone else, reset your password.
- Go to appleid.apple.com to update any of personal or security information that isn't correct or that you don't recognize.
- Check with your email address* provider to make sure that you control every email address associated with your Apple ID. If you don't control an email address, work with your email provider to regain control or use a different email address.
If you can't reset your Apple ID password or sign in
If you can't reset your Apple ID password or sign in to appleid.apple.com, go to iforgot.apple.com to start account recovery and regain access after an account recovery waiting period.
Learn more about account recovery
And see this link for further reference
If you think your Apple ID has been compromised - Apple Support