Default backend - 404 . . not sure how to solve it

Questions and Answers Deployment
18

It seems that you are getting a 404 default backend, because your app is not running properly
and is crash-looping

(node:26) DeprecationWarning: collection.ensureIndex is deprecated. Use createIndexes instead.
(Use `node --trace-deprecation ...` to show where the warning was created)
Mongoose: invoices.ensureIndex({ invoiceNumber: 1 }, { background: true })
Mongoose: products.ensureIndex({ sku: 1 }, { background: true })
Mongoose: contacts.ensureIndex({ contact_id: 1 }, { background: true })
Mongoose: purchase_orders.ensureIndex({ invoiceNumber: 1 }, { background: true })
node:internal/process/promises:246
          triggerUncaughtException(err, true /* fromPromise */);
          ^
[UnhandledPromiseRejection: This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). The promise rejected with the reason "#<Object>".] {
  code: 'ERR_UNHANDLED_REJECTION'
}
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