Can not update 10.6.8 to El Capitan.
I try to update macbookpro with 10.6.8 ios to El Capitan but get pop up in app store that says : "To make changes to your payment information, you need to upgrade your Mac to the latest version of macOS."
I can't change it anywhere, and probably it's not needed as payment info is valid I believe. What should I do to be able to update Ios?
MacBook Pro