Why does my Default Alarm app crash (closes automatically ) whenever I try to turn on my alarm?

[Windows Central Question]

My Default Alarm app crashes (closes automatically ) Whenever i tries to turn on my alarm

I am a lumia 520 (w 8.1) user for past 3 years all of a sudden my default alarm app stop working.Can't turn on any existing alarm,when i try it automatically crashes and takes me out .i have done soft Reset a couple of time .But no Use at all