Two Macintosh HD drives on Macbook Air 2019 ..?

Hi there. As you can see on the attached photo, there as two volumes on my computer named "Macintosh HD". The later one seems to be empty. In disk utility, things look even funkier, where both partitions seem to have some data on them and allocated space. This wouldn't really bother me, but I have been having trouble with the computer waking up after sleep. I was thinking this might be the reason. I recently wiped and re-installed Big Sur, and afterwards this happend. Any ideas what to do?