Process Builder not showing fields in "update records" action

Hi all, 

I'm creating a process builder on a junction object and I'm having some difficulty. There are three objects in play: Contact, Committee Enrollment (junction object) and Committee. I am trying to create a process builder on the Committee Enrollment object that when someone is enrolled in a certain committee, a boolean field on the contact record updates to true. I have tried it out in my Sandbox and it worked perfectly. When I tried it in production, it did not work. 

I have tried: 

-Spell checking the committee names

-changing field permissions to full access

-refreshing the screen

-deleting the process builder and recreating

When I recreated the process builder, I no longer see the boolean field I need to update in the "select a record related to the Committee_Enrollment__c" part for the immediate actions. I tried selecting just the contact object and not a specific field, but it will not let me move forward without selecting a specific field. 

I'm stumped--what should I do? #Automation #Process Builder #Junction Object