Xfinity tells me that Mariners TV is in my Channel lineup, but I can't access the channel

I am extremely frustrated with this situation. I received an email from Xfinity on March 26 telling me that Channel 1261/Mariners TV is "included with [my] Xfinity TV plan." But when I try to watch 1261, the TV screen shows a message saying that I must upgrade my plan.

Even today, April 4, I went online to my Xfinity account to confirm my Xfinity channel lineup. Sure enough, it shows Mariners TV on Channel 1261 as part of my channel lineup. When I share these facts with Xfinity agents, all they can tell me is that "it was/is a miscommunication" or "it has changed" since the email went out, and that the only way I can get Channel 1261 is to pay an extra $25/month.

After 38 years (!!) as an Xfinity customer who watched the Mariners on ROOT Sports and its predecessors, I have never had such an aggravating customer experience. If Xfinity is trying to get people to cut the cord and get rid of their cable subscription, this is an excellent way to do it. I am seriously considering that option.