[Q] My Fire Phone is restarting again and again :/ topic

it was working fine for a couple of weeks, but one day, I dont know really around 2 or 3 days it start to restarting again and again, someone knows the problem? how to fix it or what? sorry if my english sucks but im from venezuela :V

something else, my LTE network just work for a while, really work just 1min and after this time it just work with 2g, someone knows whats the problem?