using PHP function to compare data from MySQL database

Question

I have a signup form, in which the user has to fill in name, email, company , password and repeated password. What I am trying to do: Every company has a limited number of signups, therefore I am trying to run a query, which compares the allowed logins/signups in my company MySQL-table to the number of signed up users in my users MySQL-table. But everytime I try it, I receive the error message, that the maximum number of signups is reached (regardless of the number in the company table...).

company table:

companiesId | companiesName | companiesCode | companiesLogins
-------------------------------------------------------------
1           | Comp1        | Comp1Code      | 2
-------------------------------------------------------------
2           | Comp2        | Comp2Code      | 3

users table:

usersId | usersName | usersCode | usersCompany | usersPwd
-------------------------------------------------------------
1       | Name1     | Code1     | Comp2        | Pwd1
-------------------------------------------------------------
2       | Name2     | Code2     | Comp1        | Pwd2
-------------------------------------------------------------
3       | Name3     | Code3     | Comp1        | Pwd3

Here for example should no new signup for Comp1 be possible and 2 more for Comp2.

I am working with my PHP-Code "splitted" in different files.

File singup.php (contains specific signup stuff):

<?php if (isset($_POST["submit"])) {

$name = $_POST["name"];
$email = $_POST["email"];
$company = $_POST["company"];
$pwd = $_POST["pwd"];
$pwdRepeat = $_POST["pwdrepeat"];

require_once 'dbh.php';
require_once 'functions.php'; 

if (maxSignups($conn, $company) !== false) {
    header("location: ../page.php?error=maxsignups");
    exit();
}        ... some more if statements...

createUser($conn, $name, $email, $company, $pwd);} else {
header("location: ../login.php");
exit();}

File functions.php (contains all general functions):

<?php  
function maxSignups($conn, $company) {
    $sqlLogins = "SELECT companiesLogins AS number FROM companies WHERE companiesName = ?";
    $stmtLogins = mysqli_prepare($conn, $sqlLogins);
    mysqli_stmt_bind_param($stmtLogins, 's',$company);
    mysqli_stmt_execute($stmtLogins);
    $Logins =  mysqli_stmt_num_rows ($stmtLogins );
  
    //echo json_encode($Logins);

    $sqlUsers = "SELECT COUNT(*) AS number FROM users WHERE usersCompany = ?";
    $stmtUsers = mysqli_prepare($conn, $sqlUsers);
    mysqli_stmt_bind_param($stmtUsers, 's',$company);
    mysqli_stmt_execute($stmtUsers);
    $Users =  mysqli_stmt_num_rows ($stmtUsers );

    //echo json_encode($Users);

    if($Logins > $Users){
        $result = false;
    }
    else {
        $result = true;
    }
    return $result;

    echo json_encode($result);

I am pretty new to PHP and coding in general and because of this I was not really able to adjust some of the possible solutions, which I found here, to my problem. But from my understanding, this approach should be not to far apart (at least logically). Thanks in advance!

If I missed something out to post here feel free to tell me and I will edit the question.

---

Edit 2020/12/22: I updated my PHP. But I am facing different Problems now...

1. Only the Login query (functions.php part 1) runs and for the Users query (functions.php part 2) there occurs following error message:

Warning: mysqli_stmt_bind_param() expects parameter 1 to be mysqli_stmt, bool given in C:\xampp\htdocs...\functions.php on line 82

Warning: mysqli_stmt_execute() expects parameter 1 to be mysqli_stmt, bool given in C:\xampp\htdocs...\functions.php on line 83

Warning: mysqli_stmt_num_rows() expects parameter 1 to be mysqli_stmt, bool given in C:\xampp\htdocs...\functions.php on line 84

is there as problem with running nearly the same script back to back? even though I use different variables?

2. The first echo echo json_encode($Logins); returns 0 but it should return 1 because the name in the input form is the same like in the database table... is there still a problem with my prepared statement even though it is running (at least the first Logins part)?