Two Macintosh HD now appear in Finder.
I now have two Macintosh HD appearing in Finder. One was created 01 January 2020 and the second one was created on 18 June 2021. The one fro Jan 2020 contains Applications, Library, System, users. The Name and Extension shows as Macintosh HD. However the one that was created in June 2021, contains nothing that I can see in Finder, although if I Get Info, it does show that some of it is in use (exactly the same as in the other one. However the June 2021 created one in the Name and Extensions box says TimeMachineBackup. Can anyone tell me why this has happened and if it is using up my hard drive memory or what? Thanks.
MacBook Air 13″, macOS 11.4