For select ASINs, FBA limits the number of items that you can ship to our fulfillment centers. These limits help you avoid sending products that have high inventory levels but low customer demand. Items that have been in Amazon fulfillment centers for 6 months or more are assessed a semi-annual long-term storage fee on February 15 and April 15 of each year.
When creating a shipping plan that contains an ASIN with a quantity limit, you cannot exceed the stated maximum quantity. ASIN quantity limits may change over time based on inventory levels and sales.