Thanks for getting me back up to speed with that @Zoe7. Our tech team have advised that they can't identify any changes through Responsive that may have impacted your notifications. While we'd like the forums to be compatible with all email providers, at the moment it looks like it might not be 100% compatible with your provider. As you might imagine, there are thousands of email providers out there and one of the limitations of the platform is that it's not possible to enhance compatibility for all providers. What they have recommended is changing the email account linked to your forums account. I'm mindful you've done this before and it's not ideal because you can't access your other email address all the time. Might there be another email address you could connect to your forum account? I'm really sorry this isn't the solution you're after @Zoe7. Appreciate your understanding.
As a bit of follow up for the issue you're experiencing @CheerBear and @eth, we're wondering if you're ok with our tech team, logging into the forums with your account? This will enable them to do some more testing. If you're ok with this, all you need to do is to give us the go ahead here and we'll let them know.
Alternatively, you can provide a screenshot of the "notification settings" tab on the "settings" page. You can post the screenshot here, or email it to us here: team@saneforums.org. Please let us know what would work best for you.