How to configure TestNG in IDEA so that test classes are visible (Connot find class in classpath)?

Question

Android

There is a Gradle project for Android. As an IDE IntelliJ IDEA. The test is written, the jar with TestNG is connected. But when I run the test, I get an error:

org.testng.TestNGException: 
Cannot find class in classpath: ....

I understand that the problem is petty. But where to dig, I do not even understand. Google only offers clean for a project. Tried, doesn't help.
Test settings screenshot:

Answer 1

File -> Project structure -> Libraries