Based on nothing more than the little you've said in your post -- ie. no first hand experience whatsoever -- it sounds like the library you are using is not thread-safe.

So, as you say "if I run it in main,it runs well.", why bother trying to run it in a thread?

That is to say, if you need to do other stuff concurrently, run that other stuff in the thread, and leave this bit to run in main.