After the release of Advanced Custom Fields 6.2 there is a new section to create option pages directly in the backend.
Unfortunately there is a problem when the option “Force custom post types to use their own capabilities” is active. Although you are logged in as administrator, and even have permission according to the permissions list, you cannot access the options page list in ACF.
Apparently ACF doesn’t get along when its option pages are given their own permission names, which are obviously custom post types.