Are the messages in your webmail Spam folder? If not, check your Spam settings. Make sure that "Enable spam filtering" and "Save a copy of emails marked as spam" are both selected (see https://www.xfinity.com/support/articles/spam-filters-and-email-blocking-new-experience).
You might also check your email filters to make sure the messages aren't being intercepted there.
If the settings are correct and an employee doesn't take care of this for you here, Comcast Security Assurance should be able to help. Give them a call at 1-888-565-4329 (from https://internetsecurity.xfinity.com/help/report-abuse/). Note that this is NOT one of the general customer service numbers. The first-line reps there are sometimes not very helpful, so you may need to be persistent and keep at them until you get a satisfactory answer.
Once again my e-mail will not download...just running dots showing, but cannot get to e-mail account to send or receive messages. A constant problem with Comcast. Terrible service.