The chips you purchased should have automatically been added to your balance.
If your balance was not updated after your purchase, it may be because of a problem with the Apple or Google Play Store completing the transaction. Either company should have sent you an email confirming the purchase. We can credit your account the chips, but we just need a copy of that email. Once you have that receipt, go back to Blackjack and use the Contact Us option located in Settings and under Support, attach the receipt to the ticket and send it to us.