Converted from a basic disk to a dynamic drive in Boot Camp
Multiple people have hit the exact same issue that you described. As per Microsoft documentation, other operating systems like macOS and Linux do not understand Dynamic Disks.
Fortunately, what you did can be reverted. It's not straightforward, but it is 100% possible using the open-source utility named TestDisk. Do try it out -- there's some pain involved, but it will be worth the result.