If the dashboards have any of the same worksheets on them, then if that one worksheet was affected by an action on previous dashboard, it is going to be affected on all other dashboards. To get around this, create duplicates of the worksheet and place them each on a different dashboard.
The other thing to be aware of is what your target sheets are. It can be easy to loose track, but sometimes, it's easier to make each action one at a time so that you get the desired functionality each time. I hope this helps. If you can post an actual workbook (whether sample or the real deal), I can better help you!