I had this issue with GitLab. My email provider returned a permanent error one day (due to an issue on their end), so GitLab silently stopped sending any emails

I had this issue with GitLab. My email provider returned a permanent error one day (due to an issue on their end), so GitLab silently stopped sending any emails to my address. I checked my email in the preferences many times and had no idea it was blocked on GitLab's end. Eventually, after not getting any notifications, I contacted their customer service and was told of this hidden setting. So if you are not getting any notifications from GitLab, even though your email is correct, I suggest contacting them and asking if you have been blocked due to an error.