Help why can't I mentor robotics?

I have a sim with level 10 robotics skill AND the mentor trait. Another sim (a servo) is working on the robotics station but my mentor sim doesn't have the option to mentor and the servo can't ask the other sim to mentor. Why?  What am I doing wrong? The sims do know each other so that can't be it. Please help me!

The only reason I got her the mentor trait was so that she can spread her knowledge of robotics to others! ☹️