the two Hotspots buttons seem to disagree

When i try to activate the hotspot using the menu that you can make appear from above (the black-background one) it seems not to work (no hotspot and no hotspot symbol on the top menu appearing).
If I open setting->hotspot, there the hotspot button is deactivated (not green) while the hotspot button in the black menu is green.
It seems the button in the Settings if activated can really make the hotspot work (and make the hotspot button in the black menu green) but the hotspot button in the black menu seems to just do nothing (except cutting wifi)

On the meizu 4 with ota 12. I think the problem came with ota 11.

Sorry I already reported the bug here:
https://bugs.launchpad.net/canonical-devices-system-image/+bug/1589149
but i did not find a way to link it to the ubuntu-system-settings package, Launchpad was not cooperating... It seems there is a difference between https://bugs.launchpad.net/ubuntu/+source/ubuntu-system-settings/+filebu and https://bugs.launchpad.net/ubuntu-system-settings that launchpad dont know to make the proper link.