Strange Collisions in 2D

Hello there :) I have a small problem... I want to make a game where you are a ship trying to avoid icebergs. (Picture 1) So, the problem here is, that I have a box collider on the ship and the iceberg (I know not the best shape...) but one of the colliders seems to be stretched out along the z axis. (Picture 1) In Picture 2 and 3 you can see the Inspector of the ship and the iceberg. Maybe its worth mentioning that I am using a prefab for the iceberg...

Thanks for answering!

PS: sorry the 3rd Picture wasnt allowed anymore... I'll post it in the coments.