Fba stock unit limit?!?!

Tried to send some stock into Amazon Fba today and getting message stating :-

This product exceeds the allowed quantity for Standard-size storage. Click the Restock Limits monitor to view the maximum shipment quantity for Standard-size storage

Guessing there is a limit on the amount of stock i have with amazon? If so how many units can i have?

Any help is appreciated. Kind Regards