Here are the steps to follow to reauthorize your Amazon store:
1, Go to the Manage your apps page in Seller Central and login to your Amazon seller account as the primary user.
2, Click the Authorize new developer button and follow the authorization workflow.
3, Enter the Developer ID that applies to the account's Marketplace region:
For the US/CA/MX/BR use Developer ID "0843-0555-4555".
For EU/UK/IN/ use Developer ID "492359412835".
For AU/SG/JP use Developer ID "326471356746".
4, Enter "SKULabs" as Developer Name.
5, Follow the prompts on the page, then copy the MWS Auth Token you receive at the end of the process.
6, Navigate to SKULabs Stores Settings page and select the Amazon store you are reauthorizing.
7, Click to expand the Access credentials & integration settings section.
8, Enter the MWS Auth Token you obtained from step 5.
9, Lastly, click Save at the top right corner of the store settings page.
If you have any questions, please contact SKULabs support.