Since the new software release and update my galaxy note 20 ultra picture quality has deteriorated. Is this issue faced by anyone else?

Many of the videos which I shot from my samsung note 20 ultra phone are missing after the new software update rolled out by Samsung. This is too disappointing and great loss of data. These videos have also disappeared from the cloud where my gallery ...

Whenever I connect a charger, it first drains my phone battery and then starts charging. Tried other charger too but facing same issue. I always keep my phone optimized and on power saving mode still the battery drains