linux – Why is my mount point busy or being used? Windows to WSL file transfer

I am trying to transfer files from my Windows system to my WSL (which is running Ubuntu). I can access the files through /mnt/c, and move them to a directory in Ubuntu. But I don’t have permission to open them. This question: https://unix.stackexchange.com/questions/625938/rsync-not-copying-files-just-folder-structure/626004#626004 suggested running the line

sudo mount -t drvfs C: /mnt/c -o uid=1000,gid=1000

However when I attempt this solution I get the error:

mount: /mnt/c: c: already mounted or mount point busy.
<3>init: (424) ERROR: UtilCreateProcessAndWait:489: /bin/mount failed with status 0x2000
No error information

I have very very little experience on Linux (I’m using it for a university project) so any help would be greatly appreciated, assume (rightly) that I don’t know what I’m doing.