my goal is to automatically release the database connection after each query.

the following is the code I wrote, but when I called the interface, I reported an error Connection already released

how should I modify the code?

app.all("/resume/select", (req, res) => {
    let selectSql = "SELECT id, company, position, salary, content, dateline from work_experience w where w.userID=? and w.id=?"; //ID
    let loginUserInfo = req.session.loginUserInfo;
    let param = req.body;
    if(loginUserInfo === undefined) {
        res.json({
            code: "0000",
            message: ""
        })
    } else {
        // console.log(" loginUserInfo == ", loginUserInfo);
        pool.getConnection( (err, connection) => {
            if (err) {
                throw err;
            } else {
                connection.query(
                    selectSql,
                    [loginUserInfo.uid, param.id],
                    function (err, rows) {
                        //console.log(result);
                        //res.json(result);
                        if (err) {
                            throw err;
                        } else {
                            // console.log("loginUserInfo ==", loginUserInfo);
                            let returnData = {
                                code: "0001",
                                data: rows
                            };
                            res.json(returnData);
                        }
                        connection.release();
                    }
                )
            }
        })
    }
});


app.all("/index/message/selectAll", (req, res) => {
    let selectAdvertiseSql = "SELECT id, title, userID, salary, education, company, workPlace, dateline from advertise_message order by id DESC LIMIT ?, ?"; //ID
    let selectArticleSql = "SELECT id, title, dateline from article order by id DESC LIMIT ?, ?";
    let selectTenantSql = "SELECT id, title, dateline from tenant_message order by id DESC LIMIT ?, ?";

    let param = req.body;

    let selectParams = {
        startIndex: parseInt(param.startIndex),
        quantity: parseInt(param.quantity)
    };

    let returnData = {
        code: "",
        advertise: ""
    };

    // console.log("selectParams == ", selectParams);
    // console.log(" loginUserInfo == ", loginUserInfo);
    pool.getConnection( (err, connection) => {
        if (err) {
            throw err;
        } else {
            connection.query(
                selectAdvertiseSql,
                [selectParams.startIndex, selectParams.quantity],
                function (err, rows) {
                    //console.log(result);

                    if (err) {
                        res.json({
                            code: "0000",
                            data: ""
                        });
                    } else {
                        // console.log("loginUserInfo ==", loginUserInfo);
                        returnData["code"] = "0001";
                        returnData["advertise"] = rows;
                        // res.json(returnData);
                        connection.query(
                            selectArticleSql,
                            [selectParams.startIndex, selectParams.quantity],
                            function (err, rows) {
                                returnData["article"] = rows;
                                // res.json(returnData);

                                connection.query(
                                    selectTenantSql,
                                    [selectParams.startIndex, selectParams.quantity],
                                    function (err, rows) {
                                        returnData["tenant"] = rows;
                                        res.json(returnData);
                                    }
                                )
                            }
                        )

                    }
                    connection.release();
                }
            )
        }
    })

});