不能在自定义函数php中使用查询

Question

the directory structure is as it follows

--includes/connection.php
--includes/functions.php
index.php

in the index file the code is

require('includes/connection.php');
require('includes/functions.php');

in functions.php i required once connection.php, the function within the functions file is

function getUserInfos($someId) {
    global $link;
    $getUserInfos = mysqli_query($link, "SELECT * FROM users WHERE userId = {$someId}");


    $getUserInfos = $getUserInfos->fetch_assoc();

    return $getUserInfos['userId'];
}

in index file i want to echo the user's id but i get a blank response heres the code

<?php echo getUserInfos($someId); ?>