When I compose an email and type the first letters of a contact, the drop down list of suggestions has contacts that do not appear on my contact list.
For instance, my contact "John" changes his email address, I correct the address in contacts. When I send "John" a new email, the drop down list will have his old and new address.
I am certain that somewhere in gmail there is a setting that will only include in the drop down suggestions from names in the contact list.
Where is it?

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