If your eBay Canada orders have stopped importing to Shippo automatically, you may need to reconnect your eBay account with Shippo. You can see this by clicking on Print Shipping Label for a recent order in eBay—if you are redirected to the Shippo Orders Page and not to Step 1 to enter your package details, then you need to reconnect.
eBay Canada increased the security on their site for the continued protection of their merchants and buyers which resulted in eBay account credentials expiring.
Please reconnect your eBay merchant account to Shippo by completing the onboarding workflow here.
You can also reference the connection process here—How to Connect an eBay Store to Shippo.