A user who has permissions to use Spawn Mini, No mini, and fetch mini, some how lost the ability to use those commands when they were playing till server restart. Server restarted then they lost the ability to use commands like No Mini and Fetch Mini but can still use Spawn Mini. When that use /nomini or /fmini it just says nothing in chat and does nothing.

Could they use the commands after spawning a new one, or not at all after the restart?

If they could use them after spawning a new mini, this likely means the data referring to their previous mini was not saved in the plugin's data file. The plugin currently saves that data on server save to ensure it stays in sync with the world state, since desync used to be an issue in cases where the server did not shut down correctly, but that should be fixed in the most recent version.

What version of Spawn Mini are you using? Also, any errors in the logs?

No log errors and I am using the latest version.

From what it appears it is likely "the data referring to their previous mini was not saved in the plugin's data file". Cause after unloading the plugin, deleting the data file, and then loading it back in, they regained the ability to use the commands.

While looking through the code, I found that the only case where the fmini and nomini commands do absolutely nothing is when there is a data file desync, which is when the minicopter entity id in the plugin data file no longer matches any minicopter in the game world. The other kind of desync happens when a player-spawned minicopter is no longer in the data file, but that cannot cause this issue.

Code is already present to clean up the first kind of desync when the player uses mymini, after which point the other commands should have resumed normal function. From your original post, it doesn't sound like the player was able to use fmini and nomini after using mymini, so either that report isn't completely accurate or there is something I still don't understand.

I have made changes to make it so that when fmini and nomini identify a desync, instead of doing nothing, those commands will now clean up the desync and print the "You do not have a minicopter!" message. I submitted a pull request on GitHub for the plugin author to review and merge these changes.

I'm still not entirely sure what caused the desync in your case, but it's generally not 100% avoidable, so the best we can do is mitigations like above. One way it can happen is:

1. Server and plugin both save
2. Player spawns a mini
3. Server shuts down, which unloads the plugin (and saves the plugin's data file) but the server does not save for some reason
4. Server restarts and loads the save from #1 which does not have the mini though it is saved in the plugin data file

Based on your explanation, this is most likely what happened to cause the issue. Regarding server saving, my server is set to save between 2-5 minutes before restart so it is likely that they spawned a mini after that save resulting in the desync.
Furthermore, you are correct they did lose functionality to fmini and nomini. After removing the data file (or at least their steam64ID from it) they regained access, therefore, syncing them again.

Thank you, I appreciate the help.