Sometimes Amazon changes the dimensions of your product and this leads to a change in the FBA fee. If the newly measured size is larger, then you might have to pay a higher FBA fee for the shipping of every single unit.
Make sure you track the dimensions of your products and the FBA fee. If it changes, check if the new fee is legit and if no, open a seller support ticket and ask Amazon to remeasure the product.
The Alerts function in sellerboard automatically tracks the FBA fee and product dimension changes (as well as other important events) for all your products and notifies you if action is needed.
sellerboard is an accurate profit analytics service for amazon sellers with additional tools: follow-up mail campaigns, inventory management, reimbursements for lost & damaged stock and other FBA errors, listing change alerts. All this starting at $15 a month with a free trial.
Get 1 month of free access to sellerboard using this link:- https://bit.ly/2xgHKNl