I had that issue last year when we went to submit, it wouldn't allow it. After much frustration, I found out that the IRS had not processed our previous years return. I found this out after a long search on the IRS website. The solution was simple yet very scary as far as I'm concerned. They didn't know my previous years AGI (Adjusted Gross Income.) because they hadn't yet processed the return yet. The solution was that I had to go into turbo tax and change it by manually putting in $0 for my previous years AGI. This means I had to go in and change it in my turbo tax because turbo tax will automatically carry the AGI forward from the previous year, which is a good thing so you don't have to go looking for it in last years return, but a bad thing when the IRS takes two years off. I don't know if that may be your issue but it may be worth looking into. One way to check is to go to the IRS website and look for your previous years return and if it was processed. You could have gotten your refund even if they hadn't processed it. Anyway, good luck!
