I agree ... redo the 6252 section ... if it is done correctly the sale will only show on the form 4797 on line 4 which does not require a date ... do NOT enter the sale directly on the form 4797 entry section for a sale that did not happen in 2017.
Type in "installment sales" or "form 6252", then click the topic in the list that applies to the transaction you need to enter. This will take you directly to the start of this topic.
