expand space

I am new to Parallels. I've setup a new Win 11 machine and I started with a 256G virtual disk. After a couple of days of installing and copying files, I then expanded it to 512G (using Parallels Hardware for the VM). I've just gotten a message in Windows that I'm running out of disk space...

Using PD 12 for Mac, I imported the bootcamp partition with Windows10 and the Imported Vcamp works fine. However it is very tight for disk space (I cannot run Windows update because not enough space) but I am unable to increase its size. In Control Centre/Settings/General the Total Size is shown...