I have two problems with the Newsletters plugin.
1. I use my own email account as the test subscriber. I have never unsubscribed it, but I found that it automatically unsubscribes by itself from time to time. Is that normal?
2. As I created this test subscriber when I installed the plugin, it has the first ID number 1. (And now I have many more) Today, I found that the ID: 1 has changed to a different (unknown) email account and again, it has been unsubscribed.
3. Given these two problems, is it possible that my website has been hacked?