Mongoose can't recognize my 2dsphere index

I'm trying to add 2dSphere index for my field startLocation exists in tourSchema.Here how it looks below

   startLocation: {
      type: {
        type: String,
        default: 'Point',
        enum: ['Point']
      },
      coordinates: [Number],
      address: String,
      description: String
    }

And you can also see below what and how I've added indexes on this Schema

tourSchema.index({price:1,ratingsAverage:-1});
tourSchema.index({slug:1});
tourSchema.index({ startLocation: '2dsphere' });

Unfortunately Mongo can't recognize startLocation index.Using Mongo Compass , I'm able to see all indexes that I've created except startLocation:'2dsphere'.

Here what error that postman gives me below when I send request to getDistances method in controller

{
    "status": "error",
    "error": {
        "operationTime": "6791492473605586945",
        "ok": 0,
        "errmsg": "$geoNear requires a 2d or 2dsphere index, but none were found",
        "code": 27,
        "codeName": "IndexNotFound",
        "$clusterTime": {
            "clusterTime": "6791492473605586945",
            "signature": {
                "hash": "4LYCSBslSoLAoqj93bLXmpubBxs=",
                "keyId": "6779443539857113090"
            }
        },
        "name": "MongoError",
        "statusCode": 500,
        "status": "error"
    },
    "message": "$geoNear requires a 2d or 2dsphere index, but none were found",
    "stack": "MongoError: $geoNear requires a 2d or 2dsphere index, but none were found\n    at Connection.<anonymous> (C:\\Users\\timuc\\Downloads\\starter\\starter\\node_modules\\mongodb-core\\lib\\connection\\pool.js:443:61)\n    at Connection.emit (events.js:223:5)\n    at processMessage (C:\\Users\\timuc\\Downloads\\starter\\starter\\node_modules\\mongodb-core\\lib\\connection\\connection.js:364:10)\n    at TLSSocket.<anonymous> (C:\\Users\\timuc\\Downloads\\starter\\starter\\node_modules\\mongodb-core\\lib\\connection\\connection.js:533:15)\n    at TLSSocket.emit (events.js:223:5)\n    at addChunk (_stream_readable.js:309:12)\n    at readableAddChunk (_stream_readable.js:290:11)\n    at TLSSocket.Readable.push (_stream_readable.js:224:10)\n    at TLSWrap.onStreamRead (internal/stream_base_commons.js:181:23)"
}

I tried to add point: '2dsphere' which was recognized by mongo but I'm not satisfied.Because when I send request to method in controller that returns success but with empty array.

Here the method which was triggered in controller

  exports.getDistances = catchAsync(async(req,res,next)=>{


 const{latlng ,unit} =req.params;
    const[lat,lng] = latlng.split(',');
    if(!lat || !lng){
        new AppError('Please provide latitude and longitude in the format lat,lng',400);
    }

    const distances = await Tour.aggregate([
       {
           $geoNear: {
             near:{
                 type: 'Point',
                 coordinates : [lng*1 ,lat *1]
             },
             distanceField:'distance'         
           }
       }
    ]);

    res.status(200).json({
        status:'success',
        data:{
            data:distances
        }
    });

})

also from router you can see how I send the request URL below

tourRouter.route('/distances/:latlng/unit/:unit').get(tourController.getDistances);