Cpp-Swift Interop fails with conformance to NSObject

I have a project where I m making direct swift calls from cpp as introduced in swift5.9. Below is my swift class whose method is being invoked on cpp.

import Foundation

public class MySwiftClass
{
    public static func testInterop () -> Void {

    NSLog("----------- hey --------")
    }
}

I m able to successfully invoke 'testInterop()' in cpp with the above class, however if I add conformance to NSObject in the 'MySwiftClass' class, then the swift call fails with the error "No member named 'MySwiftClass' in namespace 'Module2'", where Module2 is my swift target.

I m not able to identify why is this happening. Any help?