The menu icon says the current privacy level, such as Public or Friends.

If you’re okay with people you’re friends with knowing your birthday, you could select Friends here instead.

If you aren’t logged in, follow the on-screen instructions to sign in now.

The menu states the current privacy level of your birthdate. For example, if your birthdate is public, you’ll see Public on the menu.

If you’re okay with friends seeing your date of birth but not random strangers, you can choose Friends instead.