“The company explains that even though you may not have signed up to use any core Meta service — such as the Facebook app, Messenger, or Instagram — it may still have your contact information.For many years, the firm asked users signing up for any of its apps to share their phone contacts, with the stated goal of helping them find friends. A side effect is that Meta, whose combined apps boast almost 3 billion daily users, has amassed an unknown but likely vast amount of personal contact information for people who have never signed up for an account, nor opted to share their information.The tool, in theory, allows a non-user to mitigate some of this damage. And although the tool is targeted at people who have never signed up for Meta’s apps, it’s likely also useful to anyone who is a user but never wanted to share this information.”
Source : Facebook Has a Hidden Tool to Delete Your Phone Number, Email