Woocommerce stopped syncing sometime in December, and now seems to occasionally sync but always incompletely and sporadically.
1) In Woocommerce Settings -> Advanced - Rest API, I could verify that ShippingEasy was most recently connecting to the store at the same time that the ShippingEasy admin said it was (4:37pm)
2) Despite this, in the ShippingEasy admin I archived that store and created a new store. I synched that store, and after 45 minutes, no orders are appearing.
3) In Woocommerce, I could verify that this new store key was also contacting the store, but this new time doesn't appear in the Shipping Easy admin (it says the last contact was 4:37pm in instead of 4:42pm).
4) I created my own REST API key in Woocommerce, and using Paw (for Mac), I could successfully retrieve the JSON listing of orders which is complete and accurate.
5) Still no orders appear in ShippingEasy.
Any help would be appreciated, though it certainly appears the issue is on your end.