You're getting "User Not Found" error because you've not actually put in your Wise Lister Remote key into your Sku Fetch List & Export Settings. We tend to see this error in 2 different cases.

1. Either you've put in your Sku Fetch Remote key there, so basically, you're telling Sku Fetch to redirect to Wise Lister but look for a Sku Fetch user in Wise Lister. It doesn't exist and therefore, user is not found. 


2. You've not put in any remote key there at all.

Sku Fetch is going to require your Wise Lister Remote Key in order to properly link to your Wise Lister account so that Wise Lister can post the items.

Please review the tutorial on connecting Sku Fetch & Wise Lister which was found in the tutorial guide which has all tutorials in order - 

Direct Link to the specific video is here - How to Connect Sku Fetch to Wise Lister Using Your Wise Lister Remote Key - CLICK HERE