Please follow the below template, it will help us to help you!
Expected Behaviour:
I expect the statistics on the home page, such as the total and blocked queries, not to reset at random moments.
Actual Behaviour:
You can do anything, close the Pi-Hole interface, press some random buttons, do exactly the same as you did the previous time it happens, but sometimes, all the stats just change back to zero's. Like there's nothing in the log. The log itself doesn't clear at all, all the requests are still inside the logs.
OK so this shows stats are being recorded correctly. I see Apache2 is running on port 80. Have you made modifications to the install in order to use a different webserver? If so you would need to re do those mods after updatig as they do not persist after an update and we do not directly support that use case.