While I agree with everything xmasbaby0 wrote, let me add an observation (probably won't be of practical assistance, sorry): sounds like you filed a federal extension, realized a few days later you needed to pay more and you followed through. That additional payment needs to be reported as a 2018 estimated payment made after 04/15 and not reported on Form 2848. Using Forms Mode, you need to get to the Tax Payments Worksheet (or follow xmasbaby0 instructions). But you also need to estimate the interest penalty for those days, and get that into your return in order to e-file (new requirement). A work around is to pretend you made the add'l payment on 04/15/2019 (separate from the extension). That should allow you to e-file. But you'll get hit up later for the interest and underpayment penalties. All this assumes you've already tried filling out a Form 2210.
