You can tell an admin about it. But it would be ultimately up to the admin on whether action is taken.
Also, sidenote for anyone reading this, most lemmy instance modlogs are publicly readable. You can see what actions your moderators are taking and this goes a huge step towards keeping mods accountable. It also gives you a greater appreciation for the absolutely fantastic mods that have to sift through all the garbage they take out. Its quite eye opening. A thankless job, and I thank the current mods for doing it.