I amended my tax return to add my 1095-A form. Why did my state return go to $0?

It should only effect Federal and the $0 on an amendment means it didn't change your original return.  

Also, you do not need to amend to add the 1095A.

Here is how to get the form 8962 filled out. Please note: You are NOT going to amend your return and you are NOT going to add a state return. These directions are quirky but will get the job done.

1.  Log into your return
2. Select that you want to add a state - this lets you into the program without the amend process starting.
3. In the top right corner, locate the Magnifying glass/search  
4. enter the exact words 1095a
5. Select the first entry Jump to 1095a
6. Fill in the 1095a information
7. Print and mail the 8962

The IRS may adjust your refund once they receive your form 8962.