Error: Could not find or load main class org.testng.remote.RemoteTestNG

I have written a test suite using TestNG. I have included only one test.java file for my service. I have created the testng.xml file as well. When I run the testng.xml file, I'm getting below error:

 Error: Could not find or load main class org.testng.remote.RemoteTestNG

Please let me know how to fix this. Created the test suite using this link. I ran the suite using this link.