[BUG] "The method of changing the texture by rename the shulker_box does not work after re-entering the save file"

[arlinkquaker]

I am attempting to create a resource pack that allows the shulker_box to be customized into dolls with different models or skins based on their names. This method enables the precise generation of dolls without any quantity restrictions, allowing me to create exactly the dolls I want.

First I made shulker_box.jem and shulker_box.png to be the default shulker_box.

Then made shulker_box2.png and shulker_box.properties ,by name "nahida":

skins.1=2
name.1=nahida

Actually, it worked. On the left is the regular shulker_box, and on the right is the one named "nahida" through the anvil.

But when I exit the save file and re-enter, nahida reverts back to the default texture.
The nahida I placed again will be displayed as "nahida" normally, but the one I placed before cannot be refreshed. After I exit again, all named shulker_boxes revert to their default textures.

I also tried searching for relevant switches in the resource pack settings, but I couldn't find a solution to this problem.

I also tried to use this method to write a variant of shulker, using renamed spawn eggs, and it worked perfectly, including exiting and re-entering the save file. However, shulker_box didn't work.

I'm not sure if the naming of this solid block is causing this reloading error. If you could fix it, I would be extremely grateful.