Podpress and Atom feed

After installing podpress I checked my feeds

https://www.feedvalidator.org/check.cgi?url=https://thealders.net/blogs/?feed=atom

and got the following error for Atom

Sorry

This feed does not validate.

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line 1, column 0: XML parsing error: <unknown>:1:0: no element found [help]

In addition, interoperability with the widest range of feed readers could be improved by implementing the following recommendation.

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Feeds should not be served with the “text/html” media type

I tried contacting the author of Podpress a week ago but have had no response and his forum does not appear to be working for registration (no captcha image for security) so I can’t leave a message there. Any help would be much appreciated