Hi,
I have problem with updating RouterOS on my hAP ac^2.
There is empty flash yet only 15% free and I can't update even manually - because system.npk is way to big.

Even tried fix-space.npk, however no luck.

Here how it looks: What can I do to fix this?

HAP AC2 does not use the flash for updates, only memory, so place the update .npk in the root, restart router and it will update just fine

No, it's still not working that way.
system.npk is downloaded only partly and after reboot, version is still the same.

Problem partly is solved by inserting even smallest usb flash drive.
At least when you can physical access to that hAP.

What is the fix-space package? And why is the version different from your ROS?

Also, you should never run user-manager or dude on such a device with the db stored on the internal flash.
In this case it is not the cause of the problem, but it very well can turn out to be a problem later.
I would recommend to do a netinstall with format of the flash.