Shopify orders do not import when I have more than 1 Shopify site
Every Shopify Store start with order number 1000 and increases for each order. You can't change the order number so if you import orders from more than 1 Shopify site some orders may not be imported (as the same order number will have been used by the other Shopify site).
To get around this you can add a prefix for the order number. You can have a different Prefix for each Shopify site. To do this select the Settings option and then General. Towards the bottom of the page is the Standards and formats section. Change the Prefix to include a value specific to each site. For example, #FLW for one site and #SED for the other site. An example is shown below: