Login on the computer to www.iCloud.com and remove the phone from your icloud device list.
Reset your Apple ID password and do not log back in on the device.
In a pinch you can call apple account security and have them revoke the certificate for your phone number from apple servers.
Reset your Apple ID password and do not log back in on the device.
In a pinch you can call apple account security and have them revoke the certificate for your phone number from apple servers.