This is probably because the frequency of notifications about content you follow is not yet set accordingly in your notification settings. You can find this by clicking on your profile picture in the top right corner.
By default, you follow groups and projects you are a member of, as well as all content you have created or commented on. You can use the "Follow" button to follow more content (or unfollow content you have already followed). On your personal dashboard, you will see an overview of all the content you follow in the bottom left.
It is best to set the notification frequency for content you follow to "Weekly" or "Never" to avoid receiving notification emails more often than you would like. If you do not want to receive notifications from the forum or other groups/projects (including within [we_faq_organisation_name] via the bell), you can also unfollow them by clicking on the "Followed" button at the top of the dashboard or on the microsite so that it becomes "Follow". You will now no longer receive unwanted notifications.