Subscriptions disappear

This may be one of the many cases where already answered questions are presented again...

Anyway, I seem to have lost the announcements of new posts made to topics I have partaken in. I can see the subscriptions in my profile, but when I mark them... it doesn't stand. I can't seem to be able to preserve the subscriptions. They disappear.

Eh?

Preferably, send me personal e-mail, as I don't get announcements...

Cheerio.