Webshop for IOS devices not working

Hey everyone!

We used to have sometimes orders which didn’t go through, but recently all of our orders from customers who has IOS device are not working.

Once they made the payment ( via paypal/or with card too i think ) they will get a white screen on confirmation page and we don’t receive the order neither funds, but they are charged.
After few working days they get the refund.

Any help would be appreciated, thanks.