I am having problems with deleted messages not syncying between my desktop, ipad and iphone devices

I did not start having this problem until a couple days ago.  I have deleted the comcast email account on both the ipad and iphone and added it back using the imap.comcast.net server and have the account set up to "Fetch New Data" automatically.  Messages are showing up timely between all three devices but deleted messages are not syncing.  Please advise.  Thanks