How to read uncomitted updates in atlas functions?

MongoDB Atlas App Services & Realm Atlas Triggers & Functions
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I have a cluster with 1 primary and 2 secondary nodes. Also, I have an atlas function witch uses a multi-document transaction. I faced a problem when I do an update and then read this document using .find() I always get not updated version of this document. Here is the function:

exports = async function({ query, headers, body}, response) {
  const collection = context.services.get("mongodb-atlas").db("zakhar").collection("w");
  
  // clean up and insert init data
  await collection.deleteMany({});
  await collection.insertOne({"name": 1, "category": "toy"});
  await collection.insertOne({"name": 2, "category": "toy"});
  await collection.insertOne({"name": 3, "category": "game"});
  await collection.insertOne({"name": 4, "category": "game"});
  
  
  const session = context.services.get("mongodb-atlas").startSession();

  const transactionOptions = {
    readPreference: "primary",
    readConcern: { level: "local" },
    writeConcern: { w: "majority" }
  };
    
  try {
    await session.withTransaction(async () => {
      await updateStatus(session);

    }, transactionOptions);
    return 'ok';
  } catch (err) {
    await session.abortTransaction();
    throw err;
  } finally {
    await session.endSession();
  }
};

async function updateStatus(session, ){
  const collection = context.services.get("mongodb-atlas").db("zakhar").collection("w");

  const countBeforeUpdate = await collection.find({"category": "toy"}, {}, { session }).toArray();
  console.log("countBeforeUpdate: " + countBeforeUpdate.length);

  const query = {"name": 1};
  const update = {"$set": {"category": "game"}};
  await collection.updateOne(query, update, { session })
      .then(result => {
        const { matchedCount, modifiedCount } = result;
        console.log("matchedCount: " + matchedCount);
        console.log("modifiedCount: " + modifiedCount);
      });
      
  const countAfterUpdate = await collection.find({"category": "toy"}, {}, { session }).toArray();
  console.log("countAfterUpdate: " + countAfterUpdate.length);

}

And it is an output, but I expect countAfterUpdate: 1

  "countBeforeUpdate: 2",
  "matchedCount: 1",
  "modifiedCount: 1",
  "countAfterUpdate: 2"

I tried to use all other transaction options(readPreference, readConcern, writeConcern), but nothing changed. Also tried to use session.startTransaction(...) instead of withTransaction()

the question on stackoverflow