Make sure you are logging into the same account that you used to file your 2016 return. It is possible to have more than one user ID linked to the same email address. You can use our Account Recovery page to make sure this isn't the case. If you haven't paid for your TurboTax fees yet, you will need to do so before it will let your view your full return.
Please refer to the following TurboTax FAQ to check on multiple accounts:
https://ttlc.intuit.com/replies/3302270