Cha Cha Mostly Tall Sliding Door Missing from BuyBuild

sirhc59​ 

Yes, there are HBD door & Cha Cha door in your build, puzzlezaddict mentioned above, and also mentioned that the door to balcony's name was Cha Cha Mostly sliding door. But you are sure that the door you installed was HBD. This is what is weird point.
Whether the door that disappeared is an HBD door or a Cha Cha makes a big difference as a bug.
As I wrote in a comment a while ago,, there is a big difference between disappearing an object having its information and disappearing an object not having its information.
Therefore, team will not be able to investigate it as a bug unless we clarify whether it is HBD or Cha Cha.
One thing I think is that the name of the door that disappeared was wrong and was renamed to Cha Cha at some point.
There had been only one type of HBD sliding door added for short walls. And the door that disappeared existed in the data before the HBD series was introduced. That's all I can say for now.

puzzlezaddict​ 

Thanks for providing the image.
The door I used is the very right door. I just can't remember the name, and the default color shown in the catalog was the blue-ish color in the top left of the color sample. It's possible that the sample was revised in an update at some point, and the name may have changed at that time. It's entirely possible that I'm just imagining things, though.
If possible, could you check my data that I made on Dec/2024 (before HBD was introduced) with an older version?
I have an original with the version information not updated (1.111.102).