Duplicate wave updating with changes on the original

I've always used "Duplicate originalwave newwave" to make different operations on a 3D wave, for example, and save multiple 2D waves. So originalwave = wave resulting from an operation.

However, something changed (even without changing my procesures or IGOR version), and now every time I make a new operation the "newwave" is getting rewritten to be equal to the "originalwave". How can that be? Can I lock "newwave" so it won't be rewritten?

EDIT:

I have a procedure (annex) that generates a panel to manipulate different 2D cuts of a 3D wave. The original wave is "map21_tnrk" and the middle panel is "map21_tnrkb". This is shown below.

I want to duplicate a given cut of panel b and make a graph with the image, so I run the following code

•Duplicate map21_tnrkb map21leftpocketXZ
•Display;DelayUpdate
•AppendImage map21leftpocketXZ
•ModifyGraph tickUnit=1,standoff=0;DelayUpdate
•ModifyGraph manTick(left)={0,0.2,0,1},manMinor(left)={0,0}
•ModifyGraph mirror=2
•ModifyGraph margin(left)=51,margin(bottom)=48,margin(right)=13,margin(top)=13
•ModifyGraph fSize=12
•ModifyGraph lblMargin(bottom)=10

However, when I change panel b of the procedure window, the duplicate is also changing.