I can't save my games on Steam Cloud

[AZA]

A few months ago, I asked for support to Steam Support about can't save game save files of Hearts of Iron 4 on Steam Cloud. The problem is that the Steam Cloud is stuck at a save file from a year ago, making it completely impossible to upload anything. At that time, Steam said me to contact Paradox Interactive, who developed HOI4, and I got support from Paradox. However, after getting support from Paradox, I said that I had never seen such a problem before and that I would have to ask Steam again for support because it seems to be a problem in the Steam Cloud. Here is the URL that I exchanged inquiries from Paradox's forum.

https://forum.paradoxplaza.com/forum/threads/i-cant-save-my-games-on-steam-cloud.1705124/page-2#post-30106415

On this URL also says that, accessing HOI4 on my computer through another account, saving the save file in Steam Cloud works fine. But if I save the save file in Steam Cloud with my account, it doesn't work at all. I've been suffering from this issue for too long, so I want an active solution.

Steam customer support simply stated that there was nothing they could do and advised me to check cases on Reddit or the Steam FAQ. I strongly emphasized to them that I had searched through various websites but could not find a case similar to mine. I also asked for an explanation of what the messages in the cloud logs mean and requested a detailed solution. However, they responded dismissively, as if dealing with a troublesome customer, giving a vague explanation like "this is what the log means" and unilaterally closed the support request. In this situation, are there any methods I can attempt myself, such as resetting the Steam Cloud?