You did something wrong, not sure what. However, a rollover (which is what a backdoor Roth is) is NOT a contribution. Don't enter any IRA contributions unless you actually made contributions separate from the conversion.
For the conversion, only enter the 1099-R from the originating bank or broker. When Turbotax asks what you did with the money, one of the choices should be a rollover or Roth conversion. Don't enter the amount again as a contribution.
