I need help figuring out how my former partner could be seeing information from my newer phone. They have referred to text messages I sent to my boss, even though they do not know or interact with my boss, so I believe they can access my texts. They have also made comments that suggest they may be seeing my photos and location. They have never had physical access to this phone, and changing my iCloud password did not solve the problem. I checked the settings and do not see anyone else listed with access. What could be causing this, and what steps should I take to secure my accounts and device?
3 Answers
A factory reset can help, but do not restore the phone from a backup until you understand what happened, since unwanted settings or apps could come back. Back up only essential photos and documents, reset the phone, install system updates, and set it up as new with a new account password. Do these changes from a safe device if possible, because someone with access to your accounts could otherwise see the new credentials.
First, identify exactly what information they know and when they learned it. If they truly know the contents of private texts, the most likely possibilities are access to your Apple account, another device signed into that account, synced messages, or access to an email or password manager. From a device you trust, review the devices signed into your Apple account, remove anything unfamiliar, change your Apple Account password, and enable two-factor authentication. Also change the passwords for your email, messaging, browser, and password-manager accounts, and sign out of other sessions. Avoid reusing passwords.
Check whether text-message syncing is enabled on another Apple device. Look under your Apple Account device list and the Messages settings for devices or forwarding options you do not recognize. Review location-sharing settings in Find My and other apps, shared photo albums, family-account settings, and any unknown configuration profiles or apps. If anything seems suspicious, take screenshots for your records before removing access.

They specifically mentioned something I texted to my boss, who they have never met. They have made other comments about my texts too. I also do not understand what a password manager is.