I have three tables, Properties, Contacts, and Companies.
Each table has a Last Unsuccessful and Last Successful contact field. Sometimes I have contact information on one or multiple of these tables (i.e. if a company owns multiple properties then I’ll create the linked relationship).
I need a way to find the maximum date of when I last spoke to someone, whether I’m looking at either of the tables.
On the table below I have two lookup fields and a natural date field for both successful and unsuccessful contacts. I referred to the thread below but not sure why I am getting an error.

