After flying I become 1 block tall while still walking

After flying with an elytra sometimes not all the time what will happen is although im walking the game thinks I'm one block tall and I can walk through one block gaps or if I jump my head will go through a block. and this is inconvienient because for example in an end city when a Shulker hits you and you one block tall you fly into the roof where you head sits their suffocating and then you die