We use MongoDB and we get this error:

```
class java.lang.Double cannot be cast to class java.lang.Long (java.lang.Double and java.lang.Long are in module java.base of loader ‘bootstrap’)

```

The stacktrace:

```
{
  "file": "Document.java",
  "method": "getLong",
  "line": 266,
  "exact": false,
  "location": "bson-3.11.0.jar",
  "class": "org.bson.Document",
  "version": "?"
},
{
  "file": "Util.kt",
  "method": "determineLastChanged",
  "line": 11,
  "exact": false,
  "location": "foobar-backend-persist-2020.47.5.jar",
  "class": "com.foobar.persist.trash.UtilKt",
  "version": "?"
},

```

Our code:

```
// com.foobar.persist.trash.UtilKt

import org.bson.Document

internal fun determineLastChanged(trashDoc: Document): Long {
  return trashDoc.getLong("_touched")
    ?: trashDoc.getLong("_created")
    ?: trashDoc.getDocument("_trash")?.getLong("deletedAt")
    ?: throw InternalTrashException("trash item without timestamp")
}

```

I know Java, but I am new to MongoDB. I worked with SQL in the past.

This error is rare, but if it happens, it is reproducible.

What could be the reason?