Peacock NBC Sports Philadelphia RSN add-on

Peacock has regional sports packages in certain areas.  One of them is Philadephia, and I would like to add this to my Peacock Premium service that I currently get (for free) through Xfinity as part to of my Internet service.  I tried going directly to the Peacock signup page after adding a payment method in Peacock (https://www.peacocktv.com/sports/nbcsports-philadelphia). It errors out trying to signup there. If I go to my account in Peacock it says I need to manage my subscription in Xfinity.  When I go to my account in Xfinity, there is no option/service that I have been able to find for the Peacock NBC Sports Philadelphia RSN add-on.

Based on Internet searches I've done, it appears the only way to get this is to cancel the free service though Xfinity and sign up for service directly through Peacock.  I'm posting here to see if there is some magic a CSR can do to add this for me.  I have no issue paying for the Peacock NBC Sports Philadelphia RSN add-on, my issue is that I have Peacock Premium already through Xfinity and cannot find any way to add it (without cancelling and resigning up directly with Peacock).

How can I signup for the Peacock NBC Sports Philadelphia RSN add-on without cancelling my currently free Peacock Premium service through Xfinity?