Why is Mongo Atlas automatically creating records?

import Transaction from '../models/Transaction'

function sendMessage() {
  const existingTx = await Transaction.exists({ transactionHash })
  if (existingTx) return 'This transaction has already happened'

  //the transaction does NOT exist
  //create it..
  const transactionAttr = {
      from,
      textMsg,
      recipient,
      senderNumber,
      transactionHash,
      createdAt: new Date(),
    }

    const transactionRecord = new Transaction(transactionAttr)
    await transactionRecord.save()
}

and Transaction is just a Mongoose modelā€¦

import mongoose from 'mongoose'

const transactionSchema = new mongoose.Schema({
  from: {
    type: String,
    required: true,
  },
  createdAt: {
    type: Date,
    required: true,
  },
  textMsg: {
    type: String,
    required: true,
  },
  recipient: {
    type: String,
    required: true,
  },
  senderNumber: {
    type: String,
    required: true,
  },
  transactionHash: {
    type: String,
    required: true,
  },
})

export default mongoose.model('Transaction', transactionSchema)

I am running this ExpressJS app on Heroku. Using Altas, and whitlelisting all IPs.

Everytime the code gets hereā€¦

const existingTx = await Transaction.exists({ transactionHash })

The Transaction is already created. I have no idea why or how this is happening. It is beyond frustrating. Iā€™ve ripped out all the code that saves the documentsā€¦ and it STILL SAVES EVERYTIME.

    const transactionRecord = new Transaction(transactionAttr)
    await transactionRecord.save()

Is there some kind of autosaving going on? Or something strange when using with Heroku that this occurs? I am really super frustrated because it makes no sense why this is happening.