Hi Андрей Снегов,
Welcome to Microsoft Community.
From a design point of view, the interface when "login" is woken up may not use the same content as the lock screen.
You mentioned that there are no problems when configuring fast startup, and I personally recommend keeping it fast start, which is also beneficial for your daily use of the device.
Besides, the situation you are experiencing is similar to that mentioned in this thread, and you can refer to it.
[Windows 11] Lock screen shows default lock screen image after - Microsoft Community
Observe whether the problem will recur under the new account.
Create a local user or administrator account in Windows - Microsoft Support
If there is anything not clear, please do not hesitate to let me know.
Best Regards,
Kyo - MSFT | Microsoft Community Support Specialist