Your account needs to be verified to get alerts. When you created the account, you should have received an email asking you to verify it.
If you've verified your email address and you're still not getting alerts, make sure you have them switched on in your account. You can find this under Account Settings and then 'Subscriptions'.
Scroll until you find 'Saved search alerts'
Here you can control whether you want notifications and how you receive them.
Good to know: Saved search alert emails are sent every 24 hours rather than immediately when a matching advert goes live.