Cannot remove ACLs from a disk

0 drwxrwxrwx+ 50 jar staff 1768 Dec 13 18:15 MacHD3

Many apps cannot write to this disk. I cannot even list it in a terminal:

JARSTUDIO:Volumes jar$ cd MacHD3

JARSTUDIO:MacHD3 jar$ sudo ls -l

total 0

ls: .: Operation not permitted

Nothing seems to work to fix it:

jar$ sudo chmod -N MacHD3

chmod: Failed to clear ACL on file MacHD3: Operation not permitted

JARSTUDIO:Volumes jar$ sudo xattr -rc MacHD3

xattr: [Errno 1] Operation not permitted: 'MacHD3

I can't see the ACL:

JARSTUDIO:MacHD3 jar$ ls -ale

total 0

ls: .: Operation not permitted

JARSTUDIO:MacHD3 jar$ sudo setfacl -bn MacHD3

sudo: setfacl: command not found

JARSTUDIO:MacHD3 jar$ ls -ldeO@ ./

drwxrwxrwx+ 50 jar staff - 1768 Dec 13 18:15 ./

0: 250769F4-8B1D-4541-B602-DF908BB54C15 allow list,add_file,search,add_subdirectory,delete_child,readattr,writeattr,readextattr,writeextattr,readsecurity

JARSTUDIO:MacHD3 jar$ sudo chflags -R nouchg ./

hflags: ./: Operation not permitted

JARSTUDIO:MacHD3 jar$ cd ../

JARSTUDIO:Volumes jar$ sudo chflags -R nouchg MacHD3

chflags: MacHD3: Operation not permitted

How do I fix this??