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?
The automatic unsubscription is possible if the unsubscription link is called by automated systems, like an antivirus. I’m working on changing that with a more secure system (it’s a common problem BTW).
The id change is not possible. About the hacking I really don’t know, and there is no reason to change only few data in a database table…