Repair your trojka by dragging a person onto the damaged part, then press the indicated button repeatedly to repair. Multiple persons can repair at once to increase repairspeed.
The interaction is a bit clunky, you need to drag the people onto the green highlighted object, then release (they change animation using a hammer), then you need to tap the indicated key on the keyboard multiple times so the green bar will fill up and the part is repaired.
i play the windows version and the bar seems to automatically fill when i drag them there, but even when i use multiple people they don't do it fast enough