Not able to run scalatest in IntelliJ on Windows OS

Question

i have a maven project and have installed scala. i have a test class which extents from Flatspec. IDE is showing a green arrow next to the test class and methods, but when i click on it, it shows "Nothing here". When i do file -> Invalidate cache/Restart, sometimes i see run, debug options against the green arrow. but when i click on run or debug, nothing happens.

after that, the option itself disappear and "Nothing here" shows next time.

I added below to pom.xml, but no use

<dependency>
  <groupId>org.scalatest</groupId>
  <artifactId>scalatest_2.10</artifactId>
  <version>2.0.M5b</version>
  <scope>test</scope>
</dependency>

scala version is as below

<properties>
        <scala.version.major>2.11</scala.version.major>
        <scala.version>2.11.8</scala.version>
        <spark.version>2.3.0</spark.version>
    </properties>

The test gets executed when i click run or debug menu on top. but it executes all the test. i want to execute specific test, which is not happening

I found the same issue being asked by someone here

https://intellij-support.jetbrains.com/hc/en-us/community/posts/206633025-Can-t-run-a-ScalaTest-FlatSpec

but i dont see the answer helpful.

can someone help? thanks.