Good morning,
Yesterday I had the exact same problem with one of my customer’s systems. The system has been in operation for two weeks. I connected to the system using the S-Net pro 2 software. Everything can be easily controlled using the integrated remote control. As soon as you use the Smart Things app, the AI wants to decide in car mode which temperatures should be used. Just like yours, 28 degrees. Apparently the AI cannot be deactivated.
Have you been able to get help in the meantime?
Greetings from Berlin,
Toralf SAMSUNG pro