No one can see your tax return or know where the error occurred if you do not describe in detail exactly what the problem is with the tax return.
Sometimes it is just easier to clear the return and start over.
If you have not paid for the online edition you are using, have not filed your tax return or registered the Free edition, then you can clear your return and start over. Click on Tax Tools on the left side of the program screen while working on the 2019 online tax return. Click on Clear & Start Over.