php upload (php 7.1)

Hey
Jeg har et upload jeg har flyttet fra en php 5.5 til en 7.1 og nu fejler den.

Warning: Invalid argument supplied for foreach()
(denne linie foreach ($_FILES['files']['name'] as $f => $name) {    )

Jeg har kigget lidt på denne fejl og syntes bare den ser ok ud.
Nogle der har et bud på en løsning ?


$valid_formats = array("jpg", "png", "gif", "pdf", "bmp", "docx", "doc");
$max_file_size = 1024*100000; //100 kb
$path = 'upload/'.$r['K_id'].'/'; // Upload directory
$count = 0;

if(isset($_POST) and $_SERVER['REQUEST_METHOD'] == "POST"){
    // Loop $_FILES to exeicute all files
    foreach ($_FILES['files']['name'] as $f => $name) {   
        if ($_FILES['files']['error'][$f] == 4) {
            continue; // Skip file if any error found
        }         
        if ($_FILES['files']['error'][$f] == 0) {             
            if ($_FILES['files']['size'][$f] > $max_file_size) {
                $message[] = "$name is too large!.";
                continue; // Skip large files
            }
            elseif( ! in_array(pathinfo($name, PATHINFO_EXTENSION), $valid_formats) ){
                $message[] = "$name is not a valid format";
                continue; // Skip invalid file formats
            }
            else{ // No error found! Move uploaded files
                if(move_uploaded_file($_FILES["files"]["tmp_name"][$f], $path.$name))           
                $count++; // Number of successfully uploaded file