Provident payout

My son worked for principal plastics and got retrenced. Mibco paid out his profident fund but send him a message on WhatsApp saying that they still need to pay him the balance that they owe him. They send him the documents he needed to fill in and he filled it in and send it back. It's been 2 months sins then but after sending numerous emails on a response of payout there has been no replies.