Thank you for your post.
If it's returning "1", "INAdditionalServices" may not be a repeating field. Count requires One Repeating Field or Several Non-Repeating Fields. You might see the Count Function listed in: https://fmhelp.filemaker.com/docs/15/en/fmp15_functions_ref.pdf
I am also going to move this thread from the FileMaker Community Feedback Space, which is specifically for input on the Community itself, to the Discussions Space where you should receive more views and potentially more advice on this topic!