Power Button on/off of RB5 not working anymore


I use the power button on/off on my Qualcomm RB5 everyday to put it to suspend mode (otherwise my Accelerometer data are blocked at 25hz because of screen use).

I have been using this button since a long time. But it is not working anymore since I flashed a new release last week…
Otherwise, everything is working OK as usual.

Short press or long press (more than 15 seconds) don’t work.