If you encounter instances where product mockup images fail to display or appear with watermarks in your Shopify store (even if you have active Starter Subscription), despite your efforts to rectify them by re-uploading label files in your Supliful account, here's a simple solution:
Delete and Republish: Begin by deleting the affected product(s) directly from your Shopify dashboard. Deleting a product in Shopify will automatically transition it to a Draft status within your Supliful account.
Refresh Product Listings: After deleting the product(s) from your Shopify dashboard, go to your Supliful profile. Locate the product(s) in the Draft section under the My Products tab, click on Pencil image to edit them, and proceed to publish them again to your Shopify store under Step 3.