What problem are you facing?

Unable to upload files with GridFSBucket in MacOS only. Works fine in Linux.

What driver and relevant dependency versions are you using? 

mongodb@4.2.2

Steps to reproduce?

const { Stream} = require('stream')
const util = require('util')
pipeline = util.promisify(Stream.pipeline);

 const { MongoClient, GridFSBucket } = require('mongodb');

client = await MongoClient.connect(`mongodb://...`, {useNewUrlParser: true, useUnifiedTopology: true});

const database = client.db('test1');
const bucket = new GridFSBucket(database, { bucketName: 'aaa' });

rs = fs.createReadStream('/var/tmp/test.txt');
ws = bucket.openUploadStream('test')
await pipeline(rs, ws)

MongoServerError: E11000 duplicate key error collection: cortex@n10.aaa.chunks index: files_id_1_n_1 dup key: { files_id: ObjectId('61c36707a7fdb6da482e14b2'), n: 0 }