Reverse String

On the Design tab, in the Editing group: Select Reverse | Reverse String to reverse the order of the points on a selected string or strings.

(Or select the Reverse String option from the Vizex right-click menu.)

If not already selected, you will be prompted to select the string(s) to reverse:

Note: For Underground Mining, this tool is located on the Mining | Underground Design tab, in the Modify group: