E-mail notifications not working

Hi,

I never receive any e-mail when someone posts a reply to a thread I’ve subscribed to. I can see the notifications in my account on the forum, but no e-mail.
I use a Gmail address. There’s nothing in the Spam folder either.
Does anyone else have this problem? Am I missing something? Is there any setting I should turn on, which I may have missed?

Thank you.

These are my notifications settings:Untitled.png