file_get_contents() has suddenly stopped working [closed]

I’m using simple_html_dom and when I get to the file_get_contents line, I get a null response. The URL is correct and this was working yesterday but not today. the code is as follows:

$sym = $symbol;       
$yahooURL="https://finance.yahoo.com/quote/$sym/history?p=$sym";
//get stock name
$data = file_get_contents($yahooURL);
//at this stage $data is returning empty
$title = preg_match('/<title[^>]*>(.*?)</title>/ims', $data, $matches) ? $matches[1] : null; 
$title = preg_replace('/[[a-zA-Z0-9. ]* | /','',$title);
$title = preg_replace('/ Stock - Yahoo Finance/','',$title);
$name = $title;
 
//get price data - use simple_html_dom.php 
$body=file_get_html($yahooURL);
if (!empty($body)) {
    $tables = $body->find('table');
 
    $dom = new DOMDocument();
    $elements[] = null;
    $dom->loadHtml($tables[0]); 
    $x = new DOMXpath($dom);
 ...

allow_url_fopen is On

Any suggestions?

I’ve checked the URL is correct. I’ve checked the $data file which comes out as blank. The $sym is correct each time.I can’t think of anything else to try.