Trying to find this episode?

[Hey Missy]

TNG, the bridge. Riker orders an ensign at the helm to plot a course, but the ensign says she can't remember how/her console isn't working properly. Riker says something like "oh that's alright, I'll take over from here and manually set the course" but he seems to be having a lapse in memory as well.
I thought it was Genesis, but it's not. I looked up and down chakoteya.net.

 

[Ensign Ricky]

You're thinking of the episode Schisms:
https://memory-alpha.fandom.com/wiki/Schisms_(episode)

 

[Hey Missy]

[Bridge]

RIKER: Ensign Rager, cartography needs a better position to study cluster FGC thirteen. Bring us about, heading one twenty three mark four.
RAGER: Aye sir. Helm won't lock to those coordinates, sir.
RIKER: First time navigating through a globular cluster, Ensign? You have got to compensate for gravimetric interference before
(Riker sits at helm and stares at the edge of the console)
RAGER: Is there something wrong, sir?
RIKER: No. I don't know. Put us back on our original heading, Ensign.

Yes! That's it. Thank you!