Guild Wars 2

I have noticed a lot of times when using my long bow on a cannon that it will be obstructed. I will see the arrows hit and it still dosnt hit instead it goes obstructed when nothing is in the way. Also on ranger Longbow five and staff ele fire five you can be on the ground and can aim up and hit the tower with a huge massive AOE. But when you are the one defending when you try to hit the ground from the same position where the the grounds aoe are hitting you in the tower. It wont let you attack showing that it is out of range. It should let you attack from both spots since there is nothing obstructing it and it is the same distance. There are a few other skills I noticed that dont work that well in wvw sometimes when running theif I will get a no valid path when there is a perfectly fine path and so on. Can we please have a patch to fix things like this?