[Dovecot] Expunge is not expunging unless it is called twice

Dovecot is requiring two "expunge" calls before it deletes an email. It just seems to ignore the first expunge call, leaving the email file in the maildir cur/ folder. Any idea why? I even waited 10 seconds after setting the Deleted flag, but still the first expunge call did nothing....

1 OK User logged in

2 select "INBOX"

• FLAGS (\Answered \Flagged \Deleted \Seen \Draft)
• OK [PERMANENTFLAGS (\Answered \Flagged \Deleted \Seen \Draft \*)] Flags permitted.
• 12 EXISTS
• 0 RECENT
• OK [UIDVALIDITY 1144082550] UIDs valid
• OK [UIDNEXT 1509] Predicted next UID 2 OK [READ-WRITE] Select completed.

3 UID STORE 1511 +FLAGS (\Deleted)

• 12 FETCH (UID 1508 FLAGS (\Deleted \Seen)) 3 OK Store completed.

4 expunge 4 OK Expunge completed.

5 expunge

• 12 EXPUNGE 5 OK Expunge completed.