ERPNext Shopify Connector Port

Hello
I have a question , to connect erpnext to shopify witch port should be keep open in erpnext server ?
Regards

Check this out.
What issue you are facing?

Reference Links
https://frappe.github.io/erpnext_shopify/
https://frappe.github.io/erpnext_shopify/install.html

if you are using v11 or higher version. the connector is available. you don’t need to install it separately.

https://frappe.github.io/erpnext_shopify/
This app has been deprecated.

yes it’s last version , issue erpnext server located behind nat in local office , if i know witch port need to communicate from shopify to erpnext i can forward that port on router to erpnext server .
Now we do all setting but sync not work.
I don’t know what is problem