In the 'CDATA' section of episode 26, there is, after a gap of a number of lines, a long line beginning 'Better mental health is something that everybody should be working towards' - this is line 257 in the Feedvalidator Report. Near the end of this long line, and at the end of the 'CDATA' section and just before the 'description' tag, there are a couple of forbidden characters. They don't show in FeedValdiator nor when looking at your feed directly but you can see them here (I've highlighted them in red):
Keep going and take care!<br /> </p>]]>
The first is Unicode 0xc2 0xac described as 'not sign' - I don't know what that means. I don't know what the second is. This sort of thing sometimes arises from composing text in a word processor and pasting it into the feed, bringing over control codes.
Both are forbidden in XML and are wrecking the feed, which cannot be read at all in iTunes. You need to remove them.