I have the same kind of issue. I have paid in December 2016. Now i was doing my tax and I launched the 2016. I did some calculation and was able to do every thing. I was able to view or print Tax Return. Later some issue happened and I was not seeing last year comparison. I deleted the 2016 file and created again.
Now i can not view or print Tax Return. It asks me to Pay. When I click on "Tax Return View or Print Return File" its pop up the Message "Ready to Pay". I have logged issue but did not got back any feedback from Ufile. It is almost 2 weeks now. Need help to resolve this issue and any idea how i can fix it.