[ubuntu] Updating mdadm – permison denied

I cannot update mdadm.conf – receiving “permission denied “.

[email protected]:~$ sudo mdadm –detail –scan >> /etc/mdadm.conf
bash: /etc/mdadm.conf: Permission denied
[email protected]:~$

What am I missing ?
I did not change anything intentionally and have no idea why it quit working and is giving
‘permissions denied ‘ error.

Here is partial output from ” ls -l ”

drwxr-xr-x 2 root root 4096 Oct 11 18:38 mdadm
-rw-r–r– 1 root root 732 Oct 13 14:12 mdadm.conf