Maybe you would have registered many devices to your one particular account. Sometimes the limit of devices that your book can be accessed simultaneously with maybe 6 or in some cases even 5 or just 2. Or if you are viewing that book in only one more device, then the publisher of that book has limited the view of that book to a single device.
When you get an error such as "license limit exceeded", do this:
Try registering your Kindle devices and applications.
Try removing the book from the device and sync it to confirm that the removal is registered with your Amazon servers.
Even if this error persists after all these efforts there might be a software issue on Amazon’s side. Click on the Contact Us of Amazon site and have the ASIN located on the product page under Product Details and also the order number with you.