Emails sent through Bigin are not posting in IMAP Sent folder

Emails sent through Bigin are not posting in IMAP Sent folder

I have set up my email to work from within Bigin using IMAP.  I am using IMAP so I can sync my email across multiple devices - phone / laptop / desktop / iPad / etc.  I want all my emails to populate my email client (outlook & iphone email) whether or not they are sent through Bigin. 

My problem is that I can send email through Bigin and they go out but they do not show up in my IMAP SENT folder, so because of that I can't see those emails anywhere other than if I am in Bigin.  Please advise.

Thank you.