Junit Parallel Execution - Query

Hello,

I am trying Paralell execution in my Junit framework. But 1 browser closes immediatley out of the 2 browsers opened. What can be the cause ?

<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.0</version>
<configuration>
<parallel>methods</parallel>
<threadCount>2</threadCount>

@Test Method calls another method which is also in the same class file.

Let me know if you need any additional details to figure out the issue.