Mutt error unexplained

When I send using this method…

:~> echo "" | mutt -s "subject" -i rad.conf

The mail is sent and received. But when I execute mutt using the same /home/ion/.muttrc and

  y:Send  q:Abort  t:To  c:CC  s:Subj  a:Attach file  d:Descrip  ?:Help 
       From: Ion <>
 Subject: test
     Fcc: =Sent
Security: None

-- Attachments                                                                                          
- I     1 /tmp/mutt-ion-a960d-1000-2503-8772594567                   [text/plain, 7bit, us-ascii, 0.1K] 

-- Mutt: Compose  [Approx. msg size: 0.1K   Atts: 1]----------------------------------------------------
CREATE failed: Permission denied

I have set the permissions on all related files to ion:user to read and write.

I used nano to create the text and it was saved to /tmp/mutt-ion-a960d-1000-3648-1163662706274734207. When I checked its permissions they were

View content : Only owner
Chenge content : Only owner

Could that be preventing mutt?