I have been getting this message for the last week or so:
IntegrationError: WooCommerce encountered an error and responded with StatusCode 0. Content: No content returned from the marketplace.
Thinking it was an issue on the Woocommerce side I updated everything on my site and still having this issue where I get this error and I do not get the status changed to Complete and there is no tracking information where it used to show up.
I checked to see if my spam plugin was the issue but even deactivated still will not work. Entered the Key numerous times and tested connection on Shipstation and all is good. Any solution or what to look at as a possible solution.