feed validation errors

Getting a bunch of validation errors on my feed. At the same time, apple stopped updating our feed. Not a total idiot when it comes to this stuff … been podcasting for over a decade. This is one part of the validation message I got:

Podcast episode count: 20
Found 20 episodes with no itunes:title tag. Apple Podcasts requires this tag.
Found 20 episodes with no itunes:summary tag, which should contain a one or more sentence summary of the episode.
Found 20 episodes with no itunes:subtitle tag, which should hold a concise, one-sentence description of the episode.
Found 20 episodes with no itunes:author tag. This will make it harder for users to find your podcast because Apple Podcasts uses this field for searches.
Found 10 episodes with no content:encoded tag, which is required if you want to displaly HTML (for example, a link) in Apple Podcasts.

Currently, you're using the category News without specifying a valid subcategory. You could select any of the following subcategories in addition:
Business News
Daily News
Entertainment News
News Commentary
Politics
Sports News
Tech News
Apple allows up to three categories per feed, and up to one subcategory per category selection. We recommend using as many categories and subcategories as possible so that your podcast can be more visible in directories.

In fact, we do use Business News and News Commentary subcategories.

The main image in the feed works fine.

Any ideas? Help is much appreciated.