AMR34 Xplained "APPS_ENDDEVICE_DEMO" Testing

Hello,
I’m trying to test the “APPS_ENDDEVICE_DEMO”
everything is fine but have a certain issue
sending data with “2” option works well but if trying to directly sleep after with “3” option it doesn’t sleep with the defined value set in conf_app.h file
it seems the timer is overwritten with an already running timer
but if i go to sleep after certain time it works fine.
any hint?
best regards
Mike