My GUI program's icon isn't display at taskbar

Hello MS team, I am a Korean working as a developer in Korea. Please understand that it may be difficult to read because I'm not good at english T.T

I am producing and distributing GUI programs using python and pyqt5 library. This program has even completed an electronic signature using DigiCert certificate. This program recently encountered a problem that the icon replaced with some other icon built into the windows(please see attached image. the icon on the rightmost side is the program I created.)

If there's anything unusual about it, the icon will appear normally when you fix the program to the taskbar, but if you disable it, the icon won't appear again.

I guess, this issue that has occurred since the Windows version was updated to the latest version. The reason I think so is that none of my program code has been modified.

Below are the actions I took to solve the problem.

1. Delete IconCache.db

• stop the explorer.exe, delete IconCache.db and restart explorer.exe.

2. set application's AUMID

• I don't know if it was set the wrong way, but it didn't work out even with the AUMID setting in the app.

If this is a real Windows 11 version problem, please suggest a solution. Windows 11 version downgrade is not possible, so I would appreciate it if you could suggest a solution among the methods that exclude version downgrade.

Have a good day! Thank you :)