Amazon Payments

I have recently moved from 1.5.5.1 to 2.0.20

I am getting this error when trying to process and order with amazon payments:

Notice: Error: Unknown column 'free_shipping' in 'field list'
Error No: 1054
INSERT INTO `oc_order_amazon` (order_id, free_shipping)

system/library/db/mysqli.php on line 4


any ideas? thanks.