We have multiple mailing lists to subscribe to and we managed that by having a checkbox field where we had:

List 1

List 2

List 3

Currently you cannot check or uncheck a singular option. If I add to the automation to check List 2, it automatically considers that I want it to uncheck List 1 and List 3. We should be able to select the targeted option alone.

I have worked around by created a different Custom Field for each list but that only goes to adding more and more fields.