Bug - Unable to sell buildings

The bug occurred midway through Mission 6 of Emperor's Testament (OXID). 

The "sell" button disappeared from all buildings. 

A screenshot is below:

<img width="2560" height="1440" alt="Image" src="https://github.com/user-attachments/assets/70b6daab-48c4-4a87-9242-5a469ccc5a31" />