I have some records like:

```js
{
  name: "Acme co."
  add4: "",
  nationalNumber: "+13412768376"
}, {
  name: "Acme Inc.",
  add4: "6345",
  nationalNumber: ""
}
```

And I'm attempting to insert them into collection, but only if they are unique. I'm checking for unique by looking for duplicate:

1. nationalNumber (if field isn't empty or null)
2. name + add4 (if both fields aren't empty or null)

I have this code in my nodeJs app:

```js
 await db.collection('mergedcompany').createIndex(
      { nationalNumber: 1},
      { unique: true },
      { partialFilterExpression: {nationalNumber: {$exists: true}}}
      );

    await db.collection('mergedcompany').createIndex(
      { name: -1, add4: -1},
      { unique: true },
      { partialFilterExpression:{ name: {$exists: true}, add4: {$exists: true}}}
      );
```

And looping over records and inserting:

```js
try {
  await db.collection('mergedcompany').insertOne(record);
} catch (e) {
  sails.log.error(e);
}
```

All records are getting inserted, even if there are duplicate fields and defined in the unique index.
If I remove the "partial" filter from the index, mongo then starts throwing errors like it should. But when I include the partial, no errors are thrown and all records are inserted, regardless if duplicate data.

What do I need to do to make this work?