Kindle Vella is a new serialized story site on Amazon. It just launched today. If you write novellas or you have a collection of stories and you're having a hard time finding a place for them you might take a look at Kindle Vella. Here's a place where you can get more information. https://www.kdpcommunity.com/s/?language=en_US
Here are two stories I'm currently running there. One is a Scifi Suspense story that begins with it snowing in July in Texas. Another is an urban fantasy in which a detective (upholder of the law) is in love and in fact engaged to a villain (breaker of the law). What could go wrong? First three episodes are free. Check them out.