[2KY]

You need to use strdel on the parameters.

pawn Код:

CMD:test( playerid, params[] )
{
    new
        user,
        action [ 24 ];
        
    if( sscanf( params, "s[24]", action ) )
        return SendClientMessage( playerid, -1, "Usage: /test [action]" );
        
    if( strcmp( action, "slap", true) == 0 )
    {
        strdel( params, 0, 4 );
        
        if( sscanf( params, "u", user ) )
            return SendClientMessage( playerid, -1, "Usage: /test slap [playerid]" );
            
        // They typed the params correct, /test slap 0 (for player ID zero)
    }
    return true;
}

Although I'm half asleep, this SHOULD work if I remember correctly.