itunes "check for new software updates automatically" is missing
I updated my computer to Mojave several months ago. Since then, iTunes no longer checks for updates for my iPhone 11. I have to manually click to check for an iOS update. When there's a new update, iTunes has a popup that tells me to go to iTunes Advanced pane and turn on "check for new software updates automatically".
However, there is no such item to turn on. See the screen shot below.
How do I turn on the auto update when it doesn't exist?
I have iTunes 12.9.5.5 and Mojave 10.14.6.
Thanks.
iMac 27", macOS 10.14