How to stop continue optimise app in Yu Yuphoria?

My mobile phone ***(Yu-Yuphoria)*** continue updating OS or optimising Apps and not stop. Actually last night when I'm going to use my mobile it displayed black screen and then I did restart the phone. At the time of restart phone as usual display **"cyanogen"** logo and then instantly going to updating mode and display **"Optimise Apps"**. I gave time but this process is not finish. I also switch off device and switch on but same alway phone going on updating mode and displaying **"Optimise Apps". I'm facing this issue last 2 days. If anyone have faced same problem then guide me on right direction. In Short how to stop this continuously updating/optimising OS ?