Why does my Lumia 830 with Windows 10 preview build restart constantly?

[Windows Central Question]

lumia 830 windows 10 preview build,errors

hello,i have nokia lumia 830,today i installed windows 10 preview build via windows insider,but phone keeps restarts every 10-15 minutes and i donth have keyboard although i installed microsoft message from store,if someone can help to solve this problem i would be very greateful.I apologize if there are errors,english is not my native language.