When doing an amended return, the meter is reset to zero and may show odd numbers until all of your changes are entered. When you're finished with your changes, the refund meter shows any additional amount owed or refunded to you. This amount is in addition to your original payment or refund shown on your originally filed tax return.
So if you see no refund, that just means you are not owed any additional refund in addition to what the original return showed.
Please see below for further explanation on how the math works when it comes to amended returns.
How does the refund math work on amendments?