[HuSs3n]

if found the mistake

pawn Код:

currentveh = GetPlayerVehicleID(playerid);
newveh = CreateVehicle(currentveh, X, Y, Z, A, 2, 0, -1);
/*
    currentveh is 'vehicle ID' not  'MODEL ID'
*/

you need to use GetVehicleModel instead

pawn Код:

CMD:plate(playerid, params[])
{
    new currentveh, newveh, msg[128], Float:X, Float:Y, Float:Z, Float:A,vModel;
    if(PlayerInfo[playerid][Padmin] >=1)
    {
        if(sscanf(params,"s[128]",msg)) return SendClientMessage(playerid, COLOR_GREEN, "USAGE: /plate <message>");
        currentveh = GetPlayerVehicleID(playerid);
        vModel = GetVehicleModel(currentveh);
        GetPlayerPos(playerid, X, Y, Z);
        GetPlayerFacingAngle(playerid, A);
        newveh = CreateVehicle(vModel, X, Y, Z, A, 2, 0, -1);
        SetVehicleNumberPlate(newveh, msg);
        DestroyVehicle(currentveh);
        PutPlayerInVehicle(playerid,newveh,0);
        return 1;
    }
    else if(PlayerInfo[playerid][Padmin] < 1)
    {
        SendClientMessage(playerid, COLOR_RED, "You must be admin to use this command");
        return 1;
    }
    return 1;
}