Second, add some logging statement so you can see whether it truly isn’t triggering or just not completing.
Third, what is Hall_Lights? If it is a Group realize that a Group’s state is the aggregate of its member’s state. So, for example if all the members are OFF and one turns ON then the Group’s state will change to ON. BUT,if a second light turns ON the Group’s state will remain unchanged and your rule will not trigger.
If you want the rule to trigger for all changes to the members you will need to use “received update”. But realize the problem there is that now the rule will trigger multiple times for each single change to one of its members.
It is indeed a group, I guess the simplest way to get this right is to have an individual rule for each item. I only have 4 lights at the moment so this is doable.