What should one do when everything one does go unproductive in one's career? How toe survive that time?

There's no such a thing. If that is happening obviously you are not doing things right. There's always ways to improve motivation, skills and ideas. But it requires a lot effort like everything in life. Also if nothing works reevaluate your path and the career you are pursuing.

Pick yourself up examine what went wrong & learn from the mistakes you made, ASK for help from somebody you trust to give you honest advice. Re-evaluate your skills

Good Luck

become an actor

choose another one.