Library notices sometimes are filtered as spam by email providers and this happens because the library sends out many notices at one time. You can prevent this from happening if you add email@example.com to your contacts or address book.
Sometimes, library notices are bounced by email providers and the notices come back to us as undeliverable so it appears that your email is no longer valid. If this happens, the library removes your email from your account and you will begin to receive telephone notifications. You should contact us, if you start receiving telephone notifications instead of email notifications.