Bad item length attribute value: -1

I’ve added two Urls to the Alternate Enclosure tag, one m3u8 and one mp4, to test the format change in players like Fountain. However, the videos from the post aren’t showing up.

When I check the rss feed: https://sasuke.es/podcast/estoespodcast at validator.livewire.io, I notice this error (the first lines in orange):

How can i fix that?

Thanks so much!

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