As part of the DLC, one needs to install a special mod in ADA using a robot workbench. Problem is, when selecting ADA to be modified, the only option shown in the workbench menu is "Legs"
Sometimes shooting ADA, using a robot repair kit and then activating the workbench fixes the issue.
Here's a video of the bug in the said "fix"
https://www.youtube.com/watch?v=NrMHySTUMmw