Do you have a different Seller Fulfilled Template on Amazon Seller Central?
If you're using a custom template in Amazon Seller Central to list your items there (meaning one other than the standard Migrated Template), it needs to be included in your SellerChamp Amazon settings so we know which template is your default there; otherwise this error is produced. Please change the shipping template on SellerChamp to match the shipping template in Amazon Seller central or eBay seller account. The screenshots below show where these settings are
Here's the setting in your SellerChamp Amazon Settings
And here is where your default template shows on Seller Central