ios – Frida: DebugSymbol.fromAddress produces objects with null fields

I am utilizing Frida to run this command on my iPhone 7 (iOS 14.4):

frida-trace -U --decorate -S lib.js -m "-[NSMutableURLRequest setValue*]" --decorate -f com.apple.AppStore

lib.js accommodates this easy helper operate:

operate backtrace() {
    return 'tBacktrace:nt' +
            Thread.backtrace(this.context, Backtracer.ACCURATE)
                .map(merchandise => {
                    var image = DebugSymbol.fromAddress(merchandise);
                    return JSON.stringify(image);
                })
                .be a part of('nt');
}

After which in onEnter of the produced handler I do that:

log(backtrace());

And all I see within the terminal is:

  1400 ms       Backtrace:
        {"tackle":"0x1069bb294","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x1069f92c4","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x106a02024","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x106a02f2c","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x106a02ddc","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x106a01d2c","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x1069f92c4","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x106a02024","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x106a02f2c","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x106a02f2c","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x106a01d2c","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x1069afaf8","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x1069afbf4","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x1069c0770","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x10695eca0","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}
        {"tackle":"0x104cd407c","identify":null,"moduleName":null,"fileName":null,"lineNumber":null}

Why is that this occurring and the way can I get module and methodology names of the decision stack gadgets?