Lambda randomly misses files, create dupes in S3 - node.js

Question

I have a lambda function to ingest images from an S3 bucket, get some metadata, store this to an AWS RDS instance and then re-upload the image. Should be simple but I fear one of the following is causing issues.
Sometimes creates duplicates
Sometime misses files
It seems to happen with larger sets of images. I uploaded sub-1000 assets and it seems to work reasonably well. 3000+ it seems to be unreliable. The function is not set to time out too early (30 seconds should be fine) it has good memory allocation 512MB (please tell me if these are false assumptions. I am an amateur at this and a novice with Lambda so please so let me know what you think I have done.
const AWS = require('aws-sdk')
const uuidv4 = require('uuid/v4');
AWS.config.update({
accessKeyId: 'XXX',
secretAccessKey: 'XXX'
})
const s3 = new AWS.S3({
signatureVersion: 'v4',
region: 'eu-west-2'
})
const hasha = require('hasha')
const { Pool, Client } = require('pg')
const pool = new Pool({
user: 'XXX',
host: 'XXX',
database: 'XXX',
password: 'XXX',
port: 5432,
})
exports.handler = async (event, context) => {
const bucket = event.Records[0].s3.bucket.name;
const key = decodeURIComponent(event.Records[0].s3.object.key.replace(/\+/g, ' '));
console.log("Processing: " + key)
//Get file
try {
const file = await s3.getObject({
Bucket: bucket,
Key: key
}).promise()
const hash = await hasha(file.Body, { algorithm: 'md5' })
const id = uuidv4()
newfile = await s3.putObject({
Bucket: 'XXX',
Key: id,
Body: file.Body,
ContentType: file.ContentType
}).promise()
var fileString = key.split('/')
var fileName = fileString[fileString.length - 1]
const text = 'INSERT INTO original(original_filename, mime, file_size, file_path, file_name, hash) VALUES($1, $2, $3, $4, $5, $6) RETURNING *'
const values = [fileName, file.ContentType, file.ContentLength, key, id, hash]
const res = await pool.query(text, values)
console.log(res.rows[0])
return "Done"
} catch (err) {
console.log("####### Error #######: ", err)
return "Error"
}
}
I am expecting that X numbers of files are uploaded and the same number are in the target bucket and within my DB table. This is not always the case and is tricky to unpick where it is going wrong. I am sure there is a more elegant way to do this.