Some properties have disappeared, It ’s all APP. You originally had 10 Properties, but now there are 6 left, and some of them have disappeared.
The first thing that comes to mind is the cache and network issues, so clear the cache first and then log in again, switch browsers, change network links, etc. The problem persists.
Another possible reason is Google’s policies, such as update iterations. Found this: https://support.google.com/analytics/answer/9167112?hl=en
Sunsetting the Google Analytics Services SDKs .
After service was fully turned down in February 2020, these legacy properties were no longer be accessible via the Google Analytics UI or API, and the associated data was deleted from Google Analytics servers.
There is no solution, you can try to contact the official to see if it is available.