Please check the following:
1) You did confirm your email by clicking Confirm link in the confirmation email we send to each email address you add to our service.
2) Look at the Spam folder or Promo folder - sometimes our emails can be put there
3) Make sure that the project you're expecting alerts from actually has email as delivery channel in project settings
4) Make sure you didn't occasionally unsubscribe from our emails. Sometimes it may happen if you accidentally click or tap so-called easy unsubscribe link in our email. Go to My Profile - Email addresses and if your email is marked as 'unsubscribed', then you need to click green 'paper plane' button - it will send you confirmation email again, and by clicking Confirm there you'll get your email back working.