Procmail giving error "Error while writing to "/var/spool/procmail/procmail.log"" in maillog.

Issue

• In maillog file, getting following procmail error:

  May  1 14:35:00 hostname postfix/qmgr[41011]: 35AC953: from=<user@domain.com>, size=3122, nrcpt=1 (queue active)
  May  1 14:35:00 hostname procmail[46292]: Error while writing to "/var/spool/procmail/procmail.log"
  May  1 14:35:00 hostname postfix/pipe[46291]: 35AC953: to=<user2@domain.com>, relay=procmail, delay=0.05, delays=0.03/0.01/0/0.01, dsn=2.0.0, status=sent (delivered via procmail service)