How to stop your phone from uploading your address book to Facebook
https://www.cnbc.com/2018/03/26/how-to-stop-your-phone-from-uploading-your-contacts-to-facebook.html
Whether you remember it or not, you may have once granted Facebook permission to store the contacts in your phone's address book. If you did, Facebook is continuously uploading these contacts to its servers.
You can find out if your phone is doing this, and stop it pretty easily.
How to stop your phone from uploading your address book to Facebook
Mar 26, 2018, 7:18pm UTC
https://www.cnbc.com/2018/03/26/how-to-stop-your-phone-from-uploading-your-contacts-to-facebook.html
>Whether you remember it or not, you may have once granted Facebook permission to store the contacts in your phone's address book. If you did, Facebook is continuously uploading these contacts to its servers.
>You can find out if your phone is doing this, and stop it pretty easily.