[member]

You keep creating the variable in the command, so you would keep getting the message:
"Prave jsis zapnul ukazovani bonusu."

Do this:

Under OnGameModeInit:

pawn Код:

new bool:bonused[MAX_PLAYERS] = true;

the command:

pawn Код:

dcmd_bonus(playerid, params[])
{
    #pragma unused params
    if(IsPlayerConnected(playerid))
    {
        if(bonused[playerid] == false)
        {
            bonused[playerid] = true;
            EnableStuntBonusForPlayer(playerid, 1);
            SendClientMessage(playerid, BARVA_ZELENA, "Prave jsis zapnul ukazovani bonusu.");
        }
        else if(bonused[playerid] == true)
        {
            bonused[playerid] = false;
            EnableStuntBonusForPlayer(playerid, 0);
            SendClientMessage(playerid, BARVA_ZELENA, "Prave jsis vypnul ukazovani bonusu.");
        }
    }
    return true;
}