Foscam F8910 motion sensor cannot be set to armed

I am using the motion sensor of this camera to switch on lights when there is motion.

I want the sensor trigger to be set on ‘device armed’, it is now on “device tripped”
When i change the scene with the trigger i created winto armed it is still after save on tripped.

Due to this my scene does not work.

Now the light is switch on and off, but when i turn off the sensor (pressing bypass) it still switches my lights back on and off.

I now have no option to switch off the motion detection at all.

When the trigger is on “device armed” the it works as it suppose to be.
I had to reinstall the camera, after this reinstall i had to recreate the scene en trigger which switches the light on mootion.
But now i cannot set it to armed any more.

What do i wrong here aand how can i fix this?

Who can help/advise?