PDF form sends FDF instead of PDF

Update

I discovered it sends PDF if opened by adobe reader at my computer, but same PDF form sends FDF if opened in Chrome browser at website

Original Question

I am using Acrobat XI Pro trial version. Adobe Acrobat offer forms in PDF documents; those forms can be submitted to the server.

"Submit" button settings:

My server code:

<?phpob_start();$file = file_get_contents("php://input"); //Gets binary PDF Data$time = microtime(true);$newfile = "./customers/" . $time . ".pdf"; //Names file based on the time to the microsecond so nothing gets overwritten.$worked = file_put_contents($newfile, $file); //Creates Fileob_end_clean();?>

I am getting an FDF data instead, not a PDF document.