[KoczkaHUN]

pawn Код:

new playerid2;

This gets never filled, it will be constantly ID 0

pawn Код:

if(GetPlayerState(playerid2) == PLAYER_STATE_DRIVER && GetPlayerState(playerid) == PLAYER_STATE_PASSENGER)

You should also check the other player is in that vehicle.

pawn Код:

GivePlayerMoney(playerid,-500);

You should check if the player has the money.

pawn Код:

new medicname[24];
new healedname[24];

You don't have to use 24, use MAX_PLAYER_NAME instead (which is 20)

pawn Код:

new string[128];

Anything more than 92 won't show on the client's screen, use 92.