You use the term “required” - DHIS2 uses a mish-mash of “Compulsory” and “Mandatory”, but I presume that is what you are talking about.
For the initial saving of a registration any empty mandatory attribute has blocked the saving and displayed a red “Required” marker underneath that/those attribute fields. I’ve just confirmed this in 2.29.
That functionality is fundamentally the same in 2.30, BUT there is a potential catch that is not obvious or displayed in any way:
YOU MUST ENSURE THAT THE AUTHORITY “Ignore compulsory/mandatory settings” (approx name) is set to NO for all users that capture this data.
So verify each of the user roles that your data capturers have, look under the “System” window, and make sure that Ignore … authority is NOT ticked.
Best regards
Calle