Remove 2nd volume after uninstalling bootcamp

I installed windows 10 on a macOS Catalina 15 bootcamp partition. When I was unable to get my bluetooth mouse or keyboard to work, I followed the uninstall procedure in Bootcamp Asst. It indicated that the bootcamp partition would be deleted and that the hard drive would be restored to its pre-bootcamp state.

However, when the process finished, Disk Utility now indicates that there are two volumes on the hard drive Apple SSD, Container disk1.

One is called "Macintosh HD" and is about 10GB in size. The second volume called "Macintosh HD Data" and it has the remainder of the 500 gb disk size.

Interestingly, only Disk Utility shows that 10GB volume. It is not displayed in File Manager or Daisy Disk.

Anyone know what this means or how I restore the pre-bootcamp single volume?

Thanks.