Making your partners call ?????

[officialtony]

I am up official. NFHS JV high school match.
I am watching play at the net for spike and block and CLEARLY see the blocker contact the net. By clearly, I mean she had both hands on top of the net and pulled it down slightly in her attempt to block. Play continued on and I kept waiting for my partner to call the net violation. I wanted to make the call myself and hesitated because I felt I shouldn't overrule my partner's non-call. I left the net play and followed the ball til the point ended. The coach asked the umpire if he had seen the net violation. He made no reply and I heard her again ask him. He again made no reply. The coach then let it go.
What is the proper protocol for this type of situation?
I don't want to overrule my partners - or get that reputation among other officials.
But I do want to do the right thing.

Thanks in advance.