How do you use custom fields with the ~Contact.FirstName~ functions?

How do you use the ~Contact.FirstName~ format on custom fields? For example if my Custom Field is “Model Number” I’ve tried ~Contact.ModelNumber~, but to no avail, it does not work.

You need to insert an underscore after the period.

~Contact._ModelNumber~

Assuming ‘ModelNumber’ is the correct database name.

If you go into an email and choose the ‘merge’ option, you can insert the merge code and check it exactly.

Thanks,
Jeff