There are many configurations of browsers and devices and while we do about best to offer cross browser/device support we do have a few issues reported each month.
If you run into a problem ordering via a Tablet/iPad then we'd recommend you switch to your Desktop or Laptop. If you have a problem with Firefox or Safari, we recommend trying Chrome or IE.
If you still don't have any luck, please let us know your browser, device and operating system when submitting a ticket.
It will help our IT department determine the issue.
Thank you.