I tried searching for a solution in the form, but I am honestly not sure what to even search for.

We have a dealer app created with several custom Account level fields

I have created an email campaign and need to pull in one of the custom fields (Scode) into the email.

I've tried using the custom merge tag creator but when I search for the field (Scode) from the CRM - it does not locate it. 

I followed the knoweldgebase articles online and can do it with default fields. But the custom ones we created - I can't seem to find those.

I hope this descirption makes sense. Any help is greatly appreciated!