I can't install windows 10...

Hi everyone.
I am trying to set up Windows 10 on Parallels 15 on a Late 2015 27" iMac running macOS Catalina 10.15.3.
Every time I attempt installation I only get so far before I get "Windows cannot install required files. The file may be corrupt or missing. Make sure all files required for installation are available, and restart the installation. Error code: 0x80070570

I am using the official Microsoft 64-bit ISO.
I have tried:
- Using the automated Parallels option and inputting the license key before starting the VM.
- Starting a new VM with no OS and booting from the ISO.
- Changing the location of the VM.
- Changing the RAM modules in the Mac. (I have tried 2x 4gb and then one 8gb on its own and another 8gb separately)

Can anyone help me? What am I doing wrong?
Thanks in advance.

 

Hi, this error might be given rise because of reasons such as corrupted ISO file, could you try to re-download it please and then check.