Spring RTS Engine

me and my friend are trying to play against each other and get good at this game, so we had a private match going but higher rank people keep joining in. we kindly ask them to leave cause we want to just play each other, but they dont listen so we kick them.

now they want to ban me again! why dont they just let me play with my friend???

Next time use a password.

indeed, if you make a public server then kick people joining ... that's not the good way to play with your friend ... add a password to make it private

You can also use a "lock" button - no one can join after its pressed. Also, people always leave when asked correctly - no one wants to spend time waiting for a battle for no good reason.
Really ultimate solution - run server locally (see downloads section on the site) and tell your friend your IP. You are really safe then :)