public OnPlayerConnect(playerid)
{
    new
        name[24],
        string[2];

    GetPlayerName(playerid, name, sizeof(name)); 
    if(sscanf(name, "{p<_>s[12]s[12]}") != 0) 
    {
        SendClientMessage(playerid, 0xFFFFFFFF, "* You have been kicked because your nickname is invalid");
        Kick(playerid);
    }
    for(new i = 0; i < 10; i ++) // we make a loop from 0 to 9
    {
        format(string, sizeof(string), "%d", i); 
        if(strfind(name, string, true) != -1) 
        {
            SendClientMessage(playerid, 0xFFFFFFFF, "* You have been kicked because your nickname had a number!");
            Kick(playerid); 
        }
    }
    return 1;
}