A cut with two pastes gives two copies. Did you change the second bar style to point to Flag2? Did you set Flag2 to yes?

With experimentation I am getting closer. Thanks. For my new tasks the only Show For information is just the Flag (e.g. Flag1 or Flag2) This seems to work. What I found however, is there seems to be a priority. I added three new columns (Flag1, Flag2 and Flag3) and create three new Bar Styles that have only Flag1, 2 or 3 in the Show For field.
If I set the Flag1 field to yes the bar style matches the Flag1 style I defined. But if I have both Flag1 and Flag2 set to Yes. It is the Flag2 style that is used. If I set all three to yes, the Flag3 bar style is used. I can deal with this.

New question. I want to set the bars length based on the start date and the end date. And I may need to change one of the these dates. But when I change the date I want the duration to change and not the other date. What I see now is I input start and end and the duration is calculated to be say 90-days. If I now change the start date, the duration stays at 90-days and the end date will also move. What do I need to do so that the duration will float as I change the dates?

The bars defined in the Bar Styles dialog box over lay one another, with bars lower down in the list overlaying bars above it.

If the Flag2 definition is below the Flag1 definition and you have both Flag1 & Flag2 set to yes, the lower (Flag2) bar overlays the Flag1 bar. You can show multiple bars if you use the thinner bar shapes if you want a task to show for both Flag1 & Flag2. If you have kept the "Task" definition, make sure you change the Show For... section and add Not Flag1, Not Flag2, Not Flag3.