I'm not receiving tag filter subscription email notifications anymore.
I did not change configuration of my subscriptions (https://stackexchange.com/users/3089209/xmojmr?tab=subscriptions) and I did not change configuration of my e-mail account.
Last mails I received were from July 24, 2018. No more emails since then. I have checked my spam folder. Everything worked fine for several years until now.
How can I troubleshoot the problem? Should I re-subscribe?