Holograms much too high | Spigot Minecraft?

I was once again on the road in my custom mobs system and continued to work. From half of the HP, a zombie should become a baby zombie. So far everything works, but the hologram (the zombie passenger) is much too high. Only when the baby zombie dies does the hologram briefly go down to where it needs to be.

There's not a lot of code to show, it's just a passenger. Only that it just has to go further down.

Maybe someone has an idea?

What kind of entity is the hologram?
An armorstand?
Just subtract the height of the armor stand so that it is below.

Thank you, it worked ^^