我正在尝试将一个新的嵌套Item文档添加到List文档中的文档数组中。它不会将Item文档添加到数组中，而是覆盖现有文档并用新文档替换它们。
代码如下：

app.post('/', async (req, res) => {
        const item = req.body.item;

        const newItem = new Item({
            name: item,
        });

        // Takes the value from the submit button
        const list = req.body.list.toLocaleLowerCase();

        await List.updateOne({ name: list }, { items: newItem });

        res.redirect('/');
    });

下面是与List交互的其余代码：

const itemsSchema = new Schema({
        name: { type: String, required: [true, `The field name is required.`] },
    });

const listsSchema = new Schema({
        name: {
            type: String,
            required: [true, `The name of the list is required.`],
        },
        items: [itemsSchema],
    });

    const List = mongoose.model('List', listsSchema);

app.get('/:list', async (req, res) => {
        // Get the requested title by the user and lower case it.
        const titleRequested = req.params.list.toLocaleLowerCase();

        // Upper case the first letter.
        const upperCasedTitle =
            titleRequested.at(0).toLocaleUpperCase() + titleRequested.slice(1);

        // Find if the list with the requested title exists in the database.
        await List.findOne({ name: titleRequested }).then(async list => {
            if (!list) {
                const newList = new List({
                    name: titleRequested,
                    items: new Item({
                        name: `You've created a ${titleRequested} list!`,
                    }),
                });

                await newList.save();

                await List.findOne({ name: titleRequested }).then(document => {
                    res.render('list', {
                        // De aca sale el value="<%= title %>"
                        title: upperCasedTitle,
                        items: document.items,
                    });
                    console.log(`${upperCasedTitle} list created succesfully.`);
                });
            } else if (list) {
                await List.findOne({ name: titleRequested }).then(document => {
                    res.render('list', {
                        // value="<%= title %>"
                        title: upperCasedTitle,
                        items: document.items,
                    });
                });
            }
        });
    });

是否有任何方法可以更新查询找到的List文档，而不覆盖现有的嵌套文档？
如果有一个特定的Model.prototype函数可以做到这一点，我还没有找到它：（