I am querying to get all articles that have a specific source name and category.

I have an article schema that looks like below.

The issue I'm facing is that, it fetches the articles with the correct source name, but it doesn't fetch for the right category. For example, if source is "cnn" and category is "sports", it fetches all articles from CNN correctly, but not with correct categories (the articles may have a categories of ['politics', 'culture'] with no sports)

const article_schema = new mongoose.Schema({
    title: {
        type: String, 
        required: true
    },
    thumbnail_url: {
        type: String, 
        required: true
    },
    summary: {
        type: String, 
        required: true
    },
    text: {
        type: String, 
        required: true
    },
    link: {
        type: String, 
        required: true
    },
    publish_date: {
        type: String, 
        required: true
    },
    source: {
        name: {
            type: String, 
            required: true
        },
        name_slug: {
            type: String, 
            required: true
        },
        link: {
            type: String, 
            required: true
        },
        display_picture_url: {
            type: String, 
            required: true
        },
        biography: {
            type: String, 
            required: true
        },
        tags: {
            type: [String], 
            required: true
        },
        rssFeeds: [{
            url: {
                type: String, 
                required: true
            },
            categories: {
                type: [String], 
                required: true
            }
        }]
    }
}); 

let getNews = async (req, res) => {
    const { sort, filter, current_page, limit, category_slug } = req.body;
    
    let articles = await Article.findOne({ 'source.name_slug': filter, categories: category_slug });

    res.setHeader('Content-Type', 'application/json');
    res.status(200).send({ articles });
}