If you have zeroes on your Form 1095-A you should leave the boxes blank. Do not enter a zero in the boxes when entering your Form 1095-A.
You can also try clearing your cache and cookies, going out of the program and coming back in, or deleting the form and reentering it, to see if that helps.
If you are entering Column B, and have a zero, you may have an error on your Form 1095-A.
Column B contains information about your "second lowest cost silver plan" (SLCSP) premium.
If column B. in Part III "Coverage Information" has a $0 or is blank for any month someone in your household had coverage from the marketplace, this is likely an error.
If you think this is the case you can use the tax tool from Healthcare.gov to determine the premium for your SLCSP. If the number is not correct, it will provide a wrong calculation of your premium tax credit.
Click here for additional information on SLCSP.
Click here for additional information on the Premium Tax Credit