I see this pattern happening one after another for tens of users and it doesn’t make much sense for so many people to subscribe and instantly unsubscribe. is there any known bug maybe?
Btw when I check these users, I see most are pretty loyal users with 70-80 even 100
% open rate.
Haven’t seen this myself – what Ghost version are you running? How are the members signing up? Through the normal portal link?
Have you tried subscribing yourself? What happens when you do that?
I regularly update it. Current * Version: 5.46.0
signing up via the blog itself.
it doesnt happen for everyone, but for a lot of people. I tried with a few of my emails, it didnt happen.
Weird
Hm, I am running a Ghost instance on 5.46.1 and don’t have any issues like that. Just tried it with a couple of test emails. All go through and stay subscribed.
Just saw your edit in your first post. You say these are pretty loyal users with a good open rate. Does that mean they have already subscribed before? I imagine, if they subscribed and unsubscribed in the same minute, they shouldn’t receive any emails? 
yes thats the strange part. these are mostly subscribes users who received a number of newsletters, opened them, clicked links in them. and now I see them as Subscribed (again, it doesnt make sense technically) and unsubscribe.
Very strange, indeed.
Are you self-hosting? If yes, have a look in the logs to see if there is something strange in there.
If you’re on Ghost Pro, I’d definitely suggest reaching out to the support, since they can probably find the issue pretty quickly.
