Units inside the course are available agains the settings options

Students have access to the Units, that they should access after responding all required assessments.

The following sections are checked in the Units settings:
- User needs to answer all required assessments and view all pages in order to access the next unit
- User also needs to pass all required assessments

Modules inside are set as Required. And still some units are accessible, even when a previous unit needs to be answered to access the next one.