Email does not delete from Hero

I have two email accounts set up on my phone.  When i delete email from my Yahoo account, it deletes the message on my phone as well.

I have a work email account.  It is a Yahoo business account and i use Outlook to manage the email.  When i delete an email in outlook it deletes it from the Yahoo business account, however that email still shows up on my phone.  Any thoughts on why this is happening and how to resolve it?