Wordpress, trying to map a gravity forms checkbox field to an advanced custom fields checkbox

I have a Wordpress site where I'm using the Advanced Custom Fields (ACF) plugin to add custom fields to the users. Then, I have a gravity form set up using the user registration add on. When the user fills out the gravity form, it updates their user information including the ACF fields. The problem I'm having is with the ACF checkbox field. When the user fills out the corresponding checkbox in the gravity form, it unchecks all of the boxes in the ACF user checkbox field. I tested it, and if only one checkbox is checked it works correctly, but when more than one is checked, it unchecks all of them. I read that Gravity forms stores the information from a checkbox differently than ACF and that's why they're not mapping correctly. Is there a code I could use to fix this?