Carlson Software Forum

cannot add breakline back to tin once deleted.
seriously WTF!
Am I alone?

So many possibilities. I don't have this problem in my 2016, so let's look at some things.
(1) Did you just delete one breakline, or all of them; or have you deleted the surface entirely?
(2) Did you delete the breakline, then closed the drawing? When you come back, then you cannot redo the breakline?
Check and make sure the surface that you want to work in is set as the current surface.
You should be able to go into the surface editor and select the add a breakline and recreate that breakline. (Make sure that your current points have been inserted at their proper Z value.)
All else fails, try reloading the software.