Issue with triggers changing

I've been having an issue with triggers for several months (and another teammate is also having this same issue). I create several shapes/textboxes on the main slide, and create layers that will show for each shape/textbox. When I create the first trigger "show layer A when user clicks box (highlighted)", it works fine. Then, I create a trigger on the second box "show layer B when user clicks box (and its the correct highlighted box)". When I create this one for Layer B, the trigger for Layer A automatically changes to B. When I change it back to A, layer/trigger B changes to A. This happens over and over. I've tried deleting all the triggers and re-creating them. I've tried deleting all the boxes on the original slide and re-creating them. I have also tried re-creating the entire slide. I've closed and re-opened Storyline (which has worked in the past). I've tried locking the boxes on the timeline after creating the trigger, before creating the next. Nothing is working. Any ideas how to get past this? We are using Storyline 3.