Thanks, Thomas.
I entered in the new installment sale (for 2019) on a new form and also entered in the payments received in 2019 for the 2016 installment sale on a second form. There were no payments received in 2019 for the 2019 sale.
I believe there should be two Forms 6252 prepared. One for the 2016 sale, to report the payments received, and one for the 2019 sale. Only one Form 6252 was prepared (for the payments received on the 2016 sale).
