TestNG-6.11.jar with parallel execution's problem?

I found Katalon using testng-6.11.jar
According this address and my experience that i couldn’t parallel executing more than 2 devices

My situation is trying parallel testing more than 2 devices , will cause the project executing hanging for a long time , wont close, and have no error . And the report show imcomplete.This is execution0.log in report file .execution0.log (9.9 KB)