It looks like you're trying to unsubscribe from an Apache Spark mailing list. Unfortunately, you have used the main mailing list address for your request (i.e. the one that is supposed to be for actual content and discussion, as opposed to administrative requests). This is bad for a few reasons.
- It clutters up the archive, as these messages stick around forever.
- It generates an unnecessary email to many thousands of people
- It doesn't actually do what you want, which is unsubscribing from the mailing list.
The good news is there are a few places where the instructions for unsubscribing are documented. You have probably come across them before, but just in case you need a refresher: