OpenCart Community

Some of my international customers are able to check out and complete their order with out choosing a shipping option, leaving me to send them an email and invoice them. Any Ideas?

OC V 2.0.20

Customer DID create an acocunt

User Agent: Mozilla/5.0 (iPad; CPU OS 9_1 like Mac OS X) AppleWebKit/600.1.4 (KHTML, like Gecko) GSA/9.0.60246 Mobile/13B143 Safari/600.1.4

USPS is set up and set for geozones.
all fields are filled in including size.
Size is set to 24x16x12 in USPS, but the sizes are also set to the actual size of the items in the products




invoice/order shows:
Sub-Total: $x.xx
: $0.00
Total: $x.xx

NOT:
Sub-Total: $x.xx
Shipping option : $x.xx
Total: $x.xx

update
pulled this from error log

2015-11-04 14:45:47 - PHP Notice: Trying to get property of non-object in /home/xxxxxxxx/public_html/catalog/model/shipping/usps.php on line 425

When I try to place an order to ship to Canada and "get shipping / tax quote" I get a pop up box with the following error

Please select the preferred shipping method to use on this order.
United States Postal Service

null - $0.00