Creating a TurboModule in the app causes it to be undefined in react native's new architecture

I am trying to create a TurboModule for my app. I don't want to create it as a separate module as mentioned over here. I want it to be part of my app So I created a RTNCalculator folder inside that a js folder and created NativeCalculator.ts file. Then in the package.json of my application I added the following code

"codegenConfig": {
    "libraries": [
      {
        "name": "NativeCalculator",
        "type": "modules",
        "jsSrcsDir": "./RTNCalculator/js"
      }
    ]
  }

My NativeCalculator.ts code

import type {TurboModule} from 'react-native/Libraries/TurboModule/RCTExport';
import {TurboModuleRegistry} from 'react-native';

export interface Spec extends TurboModule {
  add(a: number, b: number): Promise<number>;
  pickImage(): Promise<void>;
  someDummyMethod(): Promise<void>;
  addTwo(a: number, b: number): Promise<number>;
}

export default TurboModuleRegistry.get<Spec>('RTNCalculator') as Spec | null;

Then I ran ./gradlew generateCodegenArtifactsFromSchema and in the main android folder I created the following files

CalculatorModule.kt and CalculatorPackage.kt

class CalculatorPackage : TurboReactPackage() {
    override fun getModule(name: String, reactContext: ReactApplicationContext): NativeModule? {
        return if (name == CalculatorModule.NAME) {
            CalculatorModule(reactContext)
        } else {
            null
        }
    }

    override fun getReactModuleInfoProvider(): ReactModuleInfoProvider? {
        return ReactModuleInfoProvider {
            val moduleInfos: MutableMap<String, ReactModuleInfo> = HashMap()
            moduleInfos[CalculatorModule.NAME] = ReactModuleInfo(
                CalculatorModule.NAME,
                CalculatorModule.NAME,
                false,  // canOverrideExistingModule
                false,  // needsEagerInit
                true,  // hasConstants
                false,  // isCxxModule
                true // isTurboModule
            )
            moduleInfos
        }
    }
}


class CalculatorModule(context: ReactApplicationContext): NativeCalculatorSpec(context) {
    override fun getName(): String {
        return NAME
    }

    override fun add(a: Double, b: Double, promise: Promise?) {
        promise!!.resolve(a+b)
    }

    override fun pickImage(promise: Promise?) {

    }

    override fun someDummyMethod(promise: Promise?) {

    }

    override fun addTwo(a: Double, b: Double, promise: Promise?) {
        
    }

    companion object {
        const val NAME = "RTNCalculator"
    }
}

Then in MainApplication.java I added packages.add(new CalculatorPackage());

Then to use it in my App.tsx

import RTNCalculator from './RTNCalculator/js/NativeCalculator';

Now when I call the add method of RTNCalculator I get undefined. What am I missing?

I have enabled the new architecture for my app

Full source code https://github.com/BraveEvidence/TMTry