This is mainly a user community forum, not a direct route to TurboTax Support. While your email may be legitimate, we have no way of knowing if it is in a user community forum. TurboTax does send emails like that when there are changes in the account settings or a return has been accessed, so if it wasn't you, then it's possible someone has accessed your account. But you also need to be careful that it's not a scam or attempt at malware. So in the meantime, don't click on any links in the email or download any attachments. You can contact TurboTax Support by the method I'll mention below to discuss the emails and further investigate.
Right now you can log in, and go to the Intuit Account settings (that tab is in the lower part of the left column menu.) In addition to changing your password and reviewing/updating your security settings, be sure your other info in your account profile is still correct. Phone TurboTax Support on Monday so they can investigate and advise you.
Hours are currently 5AM-5PM Pacific (8AM-8PM Eastern) Monday-Friday.
You can use this contact form to get a phone number, or it may schedule a callback.