Javascript in pdf

I have created a PDF form with fields that update every time a value is entered in other fields. This works for the majority of users, but for some it doesn't.

Example:

Two Macs, both with Adobe Acrobat Reader DC. All settings regarding Forms and Javascripts are equal. Both running macOS 10.13.3. On one of them the code won't execute.

Regards,

Arve Fretheim