dmarc blocking comcast emails

So how do I fix?   I don't know about how to dig into internet/email technical details, and calling Xfinity to talk to someone is next to impossible.  

I think that in general terms, the fix is to make the sending server and the "from" address match.  ie: a comcast.net "from" address should work when using a comcast SMTP server, and a gmail "from" address should work with a gmail server. But it sounds like you may be using a gmail server with a comcast.net "from" address.  (At least that's what I think is going on when you say "Google Workspace (Gmail) email platform.".)

Our team can help, user_jdh6go! Please remember that using third-party email clients (e.g., Outlook, Apple Mail, Thunderbird, etc.) to access your Comcast.net email address can potentially expose your Xfinity ID and password to fraud and other risks. We recommend you access your Comcast email by going to Xfinity Connect. Included below is a link with additional information that may help.

Set up your Xfinity Email address with an email program

@user_jdh6go​ You may be able to adjust your Gmail/GSuite settings to use the Comcast SMTP settings.  I honestly don't know if they allow for that, but it would be nice if they did.  We're not the only consumer-oriented domain using this DMARC policy, so I would imagine this option exists.

This falls into the third-party client configurations, which is fine to use.

@strega7​

I was sending from Comcast to Comcast like I have been for decades and it still rejected the emails. What is wrong with Comcast ? We were thinking of switching to fiber which surpasses Comcast and is cheaper -so I guess that is the answer. Whenever I call them for support I have to get third level support because they don't understand the technology, truly sad...