Thats why I want a mod for it says me when I dont understand codes and stuff like that
Like I said, someone could
possibly destroy your server; problem with people having the same BL_ID is that there can be auth fails, security risks, etc. Just remember that once you set the BL_ID, you can't set it back unless they reconnect.
The way how I think of it is find their IP and add it to a list, but this entire thing is extremely dangerous and hacky, highly not recommended to be made.
Example: I one time made a bunker server that sets random bl_ids based on IPs, but anyone can set a name and even fake it. The problem with this is that I made a huge security risk and someone shut down my server with my BL_ID.