Had the same problem with Peacock despite constantly attempting to unsubscribe and mark spam. In the end I just created a filter rule to throw it in spam.
If you're in the US, I've had success by contacting customer service and threatening action under CAN-SPAM. The FTC has never really provided an easy way to file complaints or request enforcement by the public, but it seems to get their attention all the same. Now is a good time to try to exercise your legal rights against corporations before they are all executive order'ed away.
I missed that FAQ item, thanks. I've seen (and used) the "report fraud" page before, and I had seen something to suggest that it was the right place to report illegal spam, but it wasn't clear how "spam" and "fraud" were related.
I just said something like "If you don't remove me from the list within 24 hours I will report this to the FTC as a violation of US federal law." That's the easy part, the hard part is actually getting through to someone.
That might be out of concern of bad faith users abusing such a feature, such as folk who actually opt into a newsletter and then feed the results into such a filter.