New Calendar memory issue

[hw-schrauber]

My experience: I received my POCO F7 with HyperOS 2. Everything was set up correctly. The calendar app worked normally. Then I updated to HyperOS 3.0.4 (version: xiaomi.eu). After that, I updated to 3.0.9. Both versions worked fine. After updating to 3.0.11, many settings suddenly disappeared. Since then, I’ve been having issues with synchronization apps (DAVx5, etc.). They constantly report storage errors. Sometimes they write to the storage, and sometimes the storage isn’t available.
Then I installed the 3.0.4 EU version (both Recovery and Fastboot). Here, the synchronization apps work without errors. However, flashing 3.0.9/3.0.11 again brings back the same error. Could a bug have crept in between 3.0.4 and 3.0.9?

 

[hw-schrauber]

My experience: I received my POCO F7 with HyperOS 2. Everything was set up correctly. The calendar app worked normally. Then I updated to HyperOS 3.0.4 (version: xiaomi.eu). After that, I updated to 3.0.9. Both versions worked fine. After updating to 3.0.11, many settings suddenly disappeared. Since then, I’ve been having issues with synchronization apps (DAVx5, etc.). They constantly report storage errors. Sometimes they write to the storage, and sometimes the storage isn’t available.
Then I installed the 3.0.4 EU version (both Recovery and Fastboot). Here, the synchronization apps work without errors. However, flashing 3.0.9/3.0.11 again brings back the same error. Could a bug have crept in between 3.0.4 and 3.0.9?

Is there no one else having the same problem? Does anyone have any idea what might be causing this and how to fix it, if possible?