I do not know how the other plugin works. When you try to get an ACF field then ACF must be able to figure out what post to get the value from. Usually this is done by getting field inside of “The Loop”. If ACF cannot determine the post ID then you must supply it.
How you can do this depends where, how and when they code is used. Is it in a function? is it in “The Loop”? How is your code called?
