[Konstantinos]

It's spelled "state" not "statse". You have that callback already, just copy:

pawn Код:

// The below lines
    if( newstate == PLAYER_STATE_DRIVER && GetVehicleModel( GetPlayerVehicleID( playerid ) ) == 427 )
    {   
        SetPlayerArmour( playerid, 100.0 );
    }

and paste them into OnPlayerStateChange callback (Ctrl + F to find it if you want, type in the box "OnPlayerStateChange" and hit enter).

It will just look like that:

pawn Код:

public OnPlayerStateChange( playerid, newstate, oldstate )
{
    if( newstate == PLAYER_STATE_DRIVER && GetVehicleModel( GetPlayerVehicleID( playerid ) ) == 427 )
    {   
        SetPlayerArmour( playerid, 100.0 );
    }
    // Some other code you had..
    return 1;
}