I cant find a way to get a chest in the castle

[rugged hollow]

Trying to access a chest and I cant find a way to get it. It is driving me crazy

Next to the werewolf area, this chest is showing up but i have tried every way to access it and it is not showing.

This is my secodn playthrough and I still cant see the way to get it

[south lintel]

I believe that is the chest in that little shed next to Professor Kogawa's office. It has a pair of double doors leading to it, on the outside of the castle.

[rugged hollow]

How do I access it? I found it but i cant open it, use alohomora or anything

[south lintel]

You found the chest, but you can't open it? Where is it?

[rugged hollow]

I found the doors that you are talking about

[south lintel]

Only one of the doors opens. I'm pretty sure it's the right one.

[rugged hollow]

Omg you are right. Thank you sooooooooooooooooo much