[wingedhosting]

First check your logs to make sure it's not something you've done with a script, etc. Next, make sure you are running the most recent version of SAMP, if you aren't do that immediately. That's the first step, if they are crashing your server as you are saying. If they are DDoSing your server, ping flood, etc and it's very slow but not shutting down then get a DDoS protected hosts. Looks around.