I accidentally used my friend's phone number to sign in to an online store while my browser was signed in to my Google account. Since then, when my friend enters his own phone number on different websites, my email address appears automatically in the email field or profile section. This has happened on multiple sites, and we want to remove the connection completely. Is this caused by browser autofill or a saved Google account detail, and how can we stop my email from appearing?
2 Answers
Clear the browser’s autofill data rather than changing the phone number. In Chrome, open Settings, go to Autofill and passwords, review saved addresses and payment information, and delete the entry containing your email. You can also use Clear browsing data and select Autofill form data. Afterward, remove any saved login entries for those websites and have your friend enter his own email manually once.
First test whether the email is being inserted before the website loads. Open a private or guest browsing window and enter the phone number there. If your email no longer appears, the problem is local browser autofill or account synchronization, not an account association on every website. If it still appears, contact the affected websites and ask them to remove the incorrect profile information.

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