How do I cancel / amend a 1099-MISC that I filed in August '17 via QEF (Quick Employer Forms) intended for the tax year '17 - but the forms were dated 2016?

Background: In August 2017 I paid a contractor over $600.  Also in August 2017 I used Q.E.F. to create and file a 1099-MISC without noticing that the form was for 2016 instead of 2017.  The contractor noticed the mistake.

QEF currently "is not available" and "will be back soon": https://quickemployerforms.intuit.com/businessHome.htm.

I assume I just foolishly ignored that that forms were for the previous year?