从递归超时调用异步mongodb函数,我想是上下文错误

setTimeout . 但是我发现了一个上下文错误: UnhandledPromiseRejectionWarning: MongoError: Topology was destroyed

async function updateAdded(followersToAdd, username = 'blower1223', db = amng){
    const lel = await db.find({collection:COLLECTION, where: {username: username}});
    const all = await lel[0].followersAdded + followersToAdd;
    await amng.update({
        collection: COLLECTION,
        where: { username: username },
        row: { followersAdded: all }
    })
}

await amng.connect();
const loginInfo = await amng.find({ collection: COLLECTION }, {});
console.log(loginInfo);
let temp = [];
loginInfo.map((user) => {
    temp.push(new Instagram({ username: user.username, password: user.password }))
});
const users = temp;
temp = [];
let that = this;


let timerId = setTimeout(async function approveSession() {
    for (let i = 0; i < users.length; i++) {
        const client = users[i];
        await client.login();
        const req = await client.getFollowRequests();
        console.log(req);
        await updateAdded(req.length); 
        for (let i = 0; i < req.length; i++) {
            const elem = req[i];
            await client.approve({ userId: elem.node.id });
        }
    } 
    timerId = setTimeout(approveSession, 3000);
}, 3000);

我试着用 updateAdded.call(that, req.length) ,但没有解决问题。