Trying to prevent duplicate entries not working

I am fetching data from an API (array of objects) and I want to then check in the database if any of the records exist, using the url as the basis for duplicates. When it comes to inserting the new records, I get this monogoDB error:

MongoBulkWriteError: E11000 duplicate key error collection: news.news
index: sourceUrl_1 dup key: { sourceUrl:
“https://example.com/article-abc123” }

  try {
    const covidDbArticles = await News.find({ category: "Coronavirus" });
    const filterCovidDuplicates = covidData.data.news.filter(
      (covidApiSource) =>
        !covidDbArticles.some(
          (covidDatabaseSource) =>
            covidApiSource.link === covidDatabaseSource.sourceUrl
        )
    );
    if (filterCovidDuplicates.length) {
      try {
        await News.insertMany(covidNewsObj);
      } catch (err) {
        console.log("Error inserting covid data: " + err);
      }
    }
  } catch (err) {
    console.log("saving data failed: " + err);
  }