getcolumnvalue context not working

I have a drop down list for entrants to a car event. The Entrant Type can be Single, Couple or Family, with costs applied to each. Another column in the dropdown is for the number of adults. For Sngle, it is 1, Couple and Family is 2. I have a numeric field to show Number of Adults, which will be used later when calculating meal costs. To display the Number of Adults, I used the getcolumnvalue context that pops up when you enter a dot after the drop down field in the formula. I chose .GetColumnValue(“nameOrId”) and put the ID in between the brackets (“16”) but it doesn’t work when I preview the form. I tried using the form label, same result. Am I doing this correctly?

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