It's not phishing.
Please back up all data before proceeding.
Launch the Keychain Access application in any one of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad and start typing the name.
Select the login keychain from the list on the left side of the Keychain Access window. If your default keychain has a different name, select that.
If the lock icon in the top left corner of the window shows that the keychain is locked, click to unlock it. You'll be prompted for the keychain password, which is the same as your login password, unless you've changed it. If you have changed the keychain password, it will never unlock automatically unless you change its password back to the login password.
Right-click or control-click the login entry in the list. From the menu that pops up, select
Change Settings for Keychain "login"
In the sheet that opens, uncheck both boxes, if not already unchecked.
If you use iCloud Keychain, open the iCloud pane in System Preferences and uncheck the Keychain box. You'll be prompted to delete the local iCloud keychain. Confirm. Then re-check the box. Follow one of the procedures described in this support article to set up iCloud Keychain on an additional device.